Re: Idiomatic way to co-ordinate 'disconnected' services into a single transaction (ala Spring's @Transactional functionality)?
Hi Colin, no worries, responses below-
On Thu, Mar 5, 2015 at 2:31 PM, Colin Yates colin.ya...@gmail.com wrote:
Hi Jonah,
Coffee consumed, post read - thoughts emerging:
- so the 'context' is essentially a service registry as well as
run-time state?
More the latter- about transient, intermediate state rather than global
state like a registry.
A service registry could properly be a Component that depended on other
components, and then the registry could be delivered in the context map. I
usually include Components in the context map, though not the whole System
map. Flows are like functions, they should be called by Components, not
the other way around.
- if 'renew-session' and 'return-renewed-token' both needed to
execute in a single transaction that was separate to
'some-thing-else', how would that be co-ordinated - would each tx
boundary mandate a distinct flow for example
Right- generally since transaction boundaries are an edge semantic,
transaction scope should ideally be confined to a single top level edge
function, and data needed for the transaction should be prepared
beforehand- perhaps including generating primary key values separately. If
the transaction is complex and requires in-scope processing, perhaps it
should live inside the database. In theory an isolated flow could be used
*inside* transaction scope, but any complex logic occurring inside
transaction scope is a smell that perhaps transaction scope could be
rethought.
- the whole thing feels very 'state-machiney' - is that the point?
I would say data-driven.
Thanks again for sharing. I have to say that the 'flattening' of the
control, or rather conditional logic seems quite expensive. My mind
thinks in graphs not flattened lists, but maybe my resistance is just
the pain of a new paradigm...
At the moment I am slightly nervous as it seems to be conflating a
whole bunch for the win of a consistent way of moving state around.
In a way- it's just another view of an execution chain.
We get the stack-based model for free, where functions call into
functions, into other functions, etc, then are popped back out when they're
done, and conditional logic is typically embedded inside functions. When
those functions need data, it's supposed to be available in the class, or
less often, arrive on the stack, or they have to reach out onto the heap-
into global space shared by all threads. Conditional decisions aren't first
class entities- an if doesn't give you a new stack frame. etc. There are
good things about that model for certain kinds of solutions. Clojure begins
to decouple it by, e.g. by not hiding data inside classes.
A data flow model has different priorities and different costs and
benefits, and though it is less native to the JVM one can imagine a data
flow compiler that makes it a little friendlier.
Thanks for the time to respond and these questions are those of
clarity not criticism :).
Of course!
On 5 March 2015 at 16:45, Jonah Benton jo...@jonah.com wrote:
Hi Colin- a simple example that uses a flow operator would be
(- context
do-something
do-some-io
do-a-last-thing )
with
(defn do-something [context]
(let [some-data (get-in context [:path :to :data :element])
result (pure-edge-function some-data)]
(assoc-in context [:path :to :revised :data] result)))
and
(defn do-some-io [context]
(let [some-other-data (get-in context [:path :to :data :to :save])
database (get-in context [:path :to :database :resource])]
(save! database some-other-data)
context)))
Then save! can be a plain function, or
(defprotocol Saver
(save! [this data]))
(defrecord DatabaseSaver [conn ... ]
Saver
(save! ))
(defrecord AtomSaver [a ... ]
Saver
(save! ))
And context is a map of maps that contains both application state and
edge
resources that should provide or receive data.
Encoding conditional steps in a data flow presents a challenge. Several
variants for doing this are in flow operators in Clojure and there are
also
a number of third party approaches. The below is a concrete example from
an
internal library that is not open source but doesn't differ significantly
from approaches that are.
A flow looks like this:
(defflow renew
{ :startvalid-request?
valid-request?{ true valid-token? false invalid-request }
valid-token? { true ingest-token false not-authorized }
ingest-token renew-session
renew-session renewed?
renewed? { true return-renewed-token false
not-authorized
}
return-renewed-token :end
not-authorized :end
invalid-request:end })
It's a regular map with at least a :start key and an :end value. Symbols
in
a flow map are plain functions that take a context map.
Semantically, those functions represent either
[ANN] Dunaj project, an alternative core API for Clojure
I'm happy to announce a project called Dunaj [1], which provides an alternative core API for Clojure. Its main aim is to experimentally test major additions to the language. Dunaj /ˈdunaɪ/ is a set of core language experiments aimed to improve Clojure language and its core API. It deals with language features that require changes across different parts of Clojure and which cannot be evaluated in isolation. Dunaj aims to bring Clojure even more towards simplicity, consistency and performance. It is intended to be used by regular Clojure developers, either for application or library development. Dunaj was created to test 10 experiments that bring significant changes to the Clojure language. As there is a substantial number of additions and changes, I want to try a bit unconventional approach here. Before I'll release the actual library, I will introduce Dunaj's experiments in a series of individual posts. Every part states the motivation behind the experiment, introduces changes and additions to the language and demonstrates its intended use. If you do not want to miss any of this, you may want to register for a mailing list at [1] or follow @dunajproject at Twitter. -- Jozef Wagner [1] http://www.dunaj.org/ -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: Idiomatic way to co-ordinate 'disconnected' services into a single transaction (ala Spring's @Transactional functionality)?
Hi Jonah,
Coffee consumed, post read - thoughts emerging:
- so the 'context' is essentially a service registry as well as
run-time state?
- if 'renew-session' and 'return-renewed-token' both needed to
execute in a single transaction that was separate to
'some-thing-else', how would that be co-ordinated - would each tx
boundary mandate a distinct flow for example
- the whole thing feels very 'state-machiney' - is that the point?
Thanks again for sharing. I have to say that the 'flattening' of the
control, or rather conditional logic seems quite expensive. My mind
thinks in graphs not flattened lists, but maybe my resistance is just
the pain of a new paradigm...
At the moment I am slightly nervous as it seems to be conflating a
whole bunch for the win of a consistent way of moving state around.
Thanks for the time to respond and these questions are those of
clarity not criticism :).
On 5 March 2015 at 16:45, Jonah Benton jo...@jonah.com wrote:
Hi Colin- a simple example that uses a flow operator would be
(- context
do-something
do-some-io
do-a-last-thing )
with
(defn do-something [context]
(let [some-data (get-in context [:path :to :data :element])
result (pure-edge-function some-data)]
(assoc-in context [:path :to :revised :data] result)))
and
(defn do-some-io [context]
(let [some-other-data (get-in context [:path :to :data :to :save])
database (get-in context [:path :to :database :resource])]
(save! database some-other-data)
context)))
Then save! can be a plain function, or
(defprotocol Saver
(save! [this data]))
(defrecord DatabaseSaver [conn ... ]
Saver
(save! ))
(defrecord AtomSaver [a ... ]
Saver
(save! ))
And context is a map of maps that contains both application state and edge
resources that should provide or receive data.
Encoding conditional steps in a data flow presents a challenge. Several
variants for doing this are in flow operators in Clojure and there are also
a number of third party approaches. The below is a concrete example from an
internal library that is not open source but doesn't differ significantly
from approaches that are.
A flow looks like this:
(defflow renew
{ :startvalid-request?
valid-request?{ true valid-token? false invalid-request }
valid-token? { true ingest-token false not-authorized }
ingest-token renew-session
renew-session renewed?
renewed? { true return-renewed-token false not-authorized
}
return-renewed-token :end
not-authorized :end
invalid-request:end })
It's a regular map with at least a :start key and an :end value. Symbols in
a flow map are plain functions that take a context map.
Semantically, those functions represent either actions or decisions. A
function whose value in the flow map is itself a map with true and false
keys is a decision. A function whose value in the map is another function is
an action.
This particular flow performs a renewal of a web-like session token. It
runs in a Pedestal interceptor, so it receives a context map (with :request,
:response and other keys) as a parameter and at the end it populates the
:response key of the map.
The way to read this is-
0. a context map is prepared.
1. the data flow runner looks for the :start key. the value of :start is
valid-request?
2. The value of valid-request? is a map, rather than a function, so the flow
determines valid-request? is a decision function- an ordinary function that
takes a context and is expected to return true or false.
3. the flow runner executes valid-request? If it returns true, the flow
runner proceeds to valid-token? using the same context map. If false,
proceed to invalid-request
4. valid-token? is similarly a decision function, it's executed similarly
and is also expected to return true or false. invalid-request is an action.
It's expected to return a new context map- in this case it populates the
:response with a 4xx :status and some other response attributes.
5. the flow engine keeps going between keys and values until it comes to a
value of :end. Then the resulting context is the output of the flow.
The action function in the above called renew-session can do IO to renew a
user session in the database. It's copied below.
(defn renew-session [context]
(let [database(get-in context [:components :database])
session-key (get-in context [:work :session-key])
renewed?(db/renew-session! database session-key)]
(if (not (nil? renewed?))
(assoc-in context [:work :renewed-key] session-key)
context)))
It simply pulls the database connection from the context, calls into a db
specific function, db/renew-session!, which takes a connection and a key,
and could be a protocol function that accepts a Record that encapsulates a
specific storage resource, or could be
Re: [ANN] Dunaj project, an alternative core API for Clojure
On 6 March 2015 at 00:45:47, adrian.med...@mail.yu.edu (adrian.med...@mail.yu.edu) wrote: it strikes me as odd that this project would not come out of direct collaboration with Clojure's core contributors. I should point out that there's enough people in the community who do not find Clojure's core contributors, ahem, exactly open to collaborating on stuff not seen as exciting or important in their circle. Proposed features should probably go through the official channels if you are serious about getting them included in the language. Attempts to introduce major changes to clojure.core have incredibly low chances to succeed for reasons that are outside of control of Dunai's author. A completely new 3rd party project has the same low changes of being *widely* adopted but may influence clojure.core in some areas in the long run and be useful to some today. Or the day it stops being vaporware with a mailing list and no source code publicly available. -- @michaelklishin, github.com/michaelklishin -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [ANN] Dunaj project, an alternative core API for Clojure
Not sure exactly how to properly express my impression here, but it strikes me as odd that this project would not come out of direct collaboration with Clojure's core contributors. Proposed features should probably go through the official channels if you are serious about getting them included in the language. On Thursday, March 5, 2015 at 4:33:53 PM UTC-5, Jozef Wagner wrote: I'm happy to announce a project called Dunaj [1], which provides an alternative core API for Clojure. Its main aim is to experimentally test major additions to the language. Dunaj /ˈdunaɪ/ is a set of core language experiments aimed to improve Clojure language and its core API. It deals with language features that require changes across different parts of Clojure and which cannot be evaluated in isolation. Dunaj aims to bring Clojure even more towards simplicity, consistency and performance. It is intended to be used by regular Clojure developers, either for application or library development. Dunaj was created to test 10 experiments that bring significant changes to the Clojure language. As there is a substantial number of additions and changes, I want to try a bit unconventional approach here. Before I'll release the actual library, I will introduce Dunaj's experiments in a series of individual posts. Every part states the motivation behind the experiment, introduces changes and additions to the language and demonstrates its intended use. If you do not want to miss any of this, you may want to register for a mailing list at [1] or follow @dunajproject at Twitter. -- Jozef Wagner [1] http://www.dunaj.org/ -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: How to persist a value while doing do-seq
Le mercredi 4 mars 2015 22:08:13 UTC+1, Fluid Dynamics a écrit :
For examining adjacent items in a sequence, there are a few functional
(i.e., no mutable state) approaches.
When the output is a sequence with an element for each adjacent pair:
(map (fn [a b] ...) s (next s))
When the output is a sequence with an element for each adjacent pair that
meets some criterion:
(remove #{::removeme}
(map
(fn [a b]
(if (criterion a b)
(foo a b)
::removeme))
s (next s)))
OR
(for [[a b] (map vector s (next s))
:when (criterion a b)]
foo a b)
snip/
The are interesting examples.
For the use case above, I use the following instead of 'for' to avoid the
extra baggage that comes with it*:
(mapcat (fn [a b]
(when (criterion a b) [(foo a b)]))
s (next s))
But if the goal of the OP is to delete all consecutive duplicates in a
sequence then neither of these are very helpful. Instead, he could do:
user (let [s [1 1 2 2 2 1 1 3 3 3 3 4 5]]
(map first (partition-by identity s)))
;; = (1 2 1 3 4 5)
* For those who wonder what goes under the hood when you use 'for', just
try this:
user (macroexpand-1 '(for [[a b] (map vector s (next s))
:when (criterion a b)]
(foo a b)))
But beware that you might never see 'for' the same way after that :)
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clojure map to java instance of pojo class
bean? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[ANN] Indigenous, a native library helper
Hello Working with native libraries on the JVM has always been difficult because you need to deploy dynamic libraries alongside your JAR and tweak the dreaded java.library.path. When I was looking for a better solution I discovered a nice hack in gaverhae/naughtmq, by Gary Verhaegen : keep the native lib in the jar and load it when we need it. It solves the issue for ZeroMQ but I needed a more generic solution to the problem. With Gary's approval I kept the heart of the lib and I'm publishing it hoping it may be useful. As an example, I use it to load Sigar native deps. The name's Indigenous and the project is here : https://github.com/pguillebert/indigenous Let me know if you find this useful -- Philippe -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [ANN] Dunaj project, an alternative core API for Clojure
Why? One of the purposes of PyPy, for instance, was to make it easier to experiment with new features in possible Python interpreters, and that's a separate project not undertaken in direct collaboration with CPython's authors. On Thu, Mar 5, 2015 at 1:45 PM, adrian.med...@mail.yu.edu wrote: Not sure exactly how to properly express my impression here, but it strikes me as odd that this project would not come out of direct collaboration with Clojure's core contributors. Proposed features should probably go through the official channels if you are serious about getting them included in the language. On Thursday, March 5, 2015 at 4:33:53 PM UTC-5, Jozef Wagner wrote: I'm happy to announce a project called Dunaj [1], which provides an alternative core API for Clojure. Its main aim is to experimentally test major additions to the language. Dunaj /ˈdunaɪ/ is a set of core language experiments aimed to improve Clojure language and its core API. It deals with language features that require changes across different parts of Clojure and which cannot be evaluated in isolation. Dunaj aims to bring Clojure even more towards simplicity, consistency and performance. It is intended to be used by regular Clojure developers, either for application or library development. Dunaj was created to test 10 experiments that bring significant changes to the Clojure language. As there is a substantial number of additions and changes, I want to try a bit unconventional approach here. Before I'll release the actual library, I will introduce Dunaj's experiments in a series of individual posts. Every part states the motivation behind the experiment, introduces changes and additions to the language and demonstrates its intended use. If you do not want to miss any of this, you may want to register for a mailing list at [1] or follow @dunajproject at Twitter. -- Jozef Wagner [1] http://www.dunaj.org/ -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- Ben Wolfson Human kind has used its intelligence to vary the flavour of drinks, which may be sweet, aromatic, fermented or spirit-based. ... Family and social life also offer numerous other occasions to consume drinks for pleasure. [Larousse, Drink entry] -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [ANN] Dunaj project, an alternative core API for Clojure
Yeah, I'm excited to see some of the 10 write-ups. What's the ETA on the first one? On Thu, Mar 5, 2015 at 6:02 PM, Alex Miller a...@puredanger.com wrote: I'm happy to see experiments if we can learn something useful. Can't really judge more till the posts are out. Seems perfectly possible that something promising could get a design page and move towards inclusion in some way. Alex -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [ANN] Dunaj project, an alternative core API for Clojure
Just a quick glance at the example project shows integrated type definitions. I'm curious for sure. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [ANN] Dunaj project, an alternative core API for Clojure
Where is this example project? On Thu, Mar 5, 2015 at 7:40 PM, Ivan L ivan.laza...@gmail.com wrote: Just a quick glance at the example project shows integrated type definitions. I'm curious for sure. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [ANN] Dunaj project, an alternative core API for Clojure
I'm happy to see experiments if we can learn something useful. Can't really judge more till the posts are out. Seems perfectly possible that something promising could get a design page and move towards inclusion in some way. Alex -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: clojure map to java instance of pojo class
On Thu, Mar 5, 2015 at 2:42 AM, Xiangtao Zhou tao...@gmail.com wrote:
hi all,
is there some library or simple way to do it like the function
map-to-pojo in the following code ?
java code
class A{
public int a;
public String b;
}
clojure code
(def a {:a 1 :b 2})
(def b (map-to-pojo a A))
(instance? b A)
You'll want to use clojure.java.data: https://github.com/clojure/java.data/
Assuming class A with an integer field, with an appropriate getter and
setter.
user (require '[clojure.java.data :as d])
nil
user (d/to-java A {:x 1})
#A foo.A@6b91ca5c
user (.getX *1)
1
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GSOC 2015 — tools.reader.cljs
Hello everyone, I am an undergraduate student looking to participate in the GSOC this summer. I've been looking through the project ideas http://dev.clojure.org/display/community/Project+Ideas on the Clojure Development site, and the one that looks most interesting to me is implementing tools.reader in cljs. That webpage suggests contacting David Nolen and/or Nicola Mometto as mentors, but I'm not sure how to contact either of them. Does anyone know how I could contact either of those two? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: Who's using Clojure?
The question of using may have different meanings depending on your definition - if you include using libraries or frameworks built with Clojure (partly or in whole) you could include all the companies who deploy, for example, Apache Storm or use some of Puppet Labs' tools. The consultancy ThoughtWorks has put Clojure on their radar - several Clojure and ClojureScript libraries are also listed (Core Async, Om, Reagent.) I can't vouch for the consultancy itself but I think it is telling that Clojure has a number of technologies listed there. Given the fact that, as a hosted language, Clojure is very different than say, Go or Erlang, where the language ecosystem (runtimes, libraries, etc.) is entirely dependent on the language's popularity in order for it to expand into new environments and remain viable. Given that Java (and the JVM), CLR, and Javascript effectively boost Clojure into new contexts for (mostly) free it can play nice along with existing languages and their momentum. See also: React Native. Additionally, consider that ClojureScript and Om have strongly influenced the React community w.r.t. immutability, I'd say that counts as a big win for Clojure. IMHO, job boards are effectively looking backwards in time. It isn't the place to look if you are trying new things or being innovative. Sure, if you want to hire some easily replaceable tool go for Java... what could possibly go wrong? :-) Alan On Thursday, March 5, 2015 at 7:47:41 AM UTC-8, Michael Richards wrote: I'm about to start training 4 devs on my team at Oracle in Clojure. My manager is very nervous about putting Clojure into the product. I'm forging on regardless :) I rewrote some components of our product in Clojure in my spare time, mainly as a proof of concept that we could do some of our analytics in the streaming model rather than in the data warehousing model. As sometimes happens, the POC was so simple and fast that the team is now interested in productizing it. In our last 1-1 meeting, my manager told me he had searched LinkedIn for Clojure and only got 9000 matches. Whereas his search for Java turned up 80 million or some such. My rebuttal is that those are the 9000 smartest developers, so you should be trying to recruit them. --mike -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: How to persist a value while doing do-seq
For the particular use case of removing duplicates there is a new dedupe in Clojure 1.7: http://crossclj.info/fun/clojure.core/dedupe.html Alex -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: GSOC 2015 — tools.reader.cljs
The email they use to correspond on this group are: David - dnolen.li...@gmail.com Nicola - brobro...@gmail.com Daniel (GSoC organizer for Clojure), would there be any objection to including email addresses of mentors on the Clojure GSOC 2015 projects page? The question of what to do if someone is interested in a project has come up multiple times recently. Andy On Thu, Mar 5, 2015 at 5:17 PM, Matthew West matthewwest...@gmail.com wrote: Hello everyone, I am an undergraduate student looking to participate in the GSOC this summer. I've been looking through the project ideas http://dev.clojure.org/display/community/Project+Ideas on the Clojure Development site, and the one that looks most interesting to me is implementing tools.reader in cljs. That webpage suggests contacting David Nolen and/or Nicola Mometto as mentors, but I'm not sure how to contact either of them. Does anyone know how I could contact either of those two? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: How to model a rectangle?
Looks interesting, thanks! On Thu, Mar 5, 2015 at 4:43 PM, Leon Grapenthin grapenthinl...@gmail.com wrote: (defn rect2 [x y width height] (let [lr [(+ width x) (+ width y)]] (reify Rect (upper-left [_] [x y]) (lower-right [_] lr) (area [_] (* width height) Just a quick remark: In JavaScript I purposefully did not use `width` and `height` for calculating area. That way the garbage collector can release them, making objects smaller. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
How to model a rectangle?
Disclaimer: I’ve never done *any* Clojure programming, but I’m curious.
Here’s how I may model an on-screen rectangle in JavaScript, a classless
object oriented language:
let createRectangle = function (x, y, width, height) {
return {
get upperLeft() {
return [x, y];
},
get lowerRight() {
return [x + width, y + height];
},
get area() {
return width * height;
}
};
};
let r = createRectangle(0, 0, 50, 20);
let s = createRectangle(10, 20, 40, 5);
console.log(r.upperLeft, r.lowerRight, r.area);
console.log(s.upperLeft, s.lowerRight, s.area);
Now I run the profiler. I discover that in the inner loop of my program
there are lots of calls needing the upper left and the lower right
coordinates. So I change the inner workings of the object to store these
instead:
let createRectangle = function (x, y, width, height) {
let upperLeft = [x, y], lowerRight = [x + width, y + height];
return {
get upperLeft() {
return upperLeft;
},
get lowerRight() {
return lowerRight;
},
get area() {
return (lowerRight[0] - upperLeft[0]) *
(lowerRight[1] - upperLeft[1]);
}
};
};
Boom: Now the program is twice as fast, and - what gives me great
comfort - I know that this change breaks nothing. I only had to edit the
code in *one* module. I didn’t need to think too much about efficiency
of data structures in the beginning. I could just start going, then
optimize in the end.
*Can I program in a similar way using Clojure?*
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Re: How to model a rectangle?
You could use Clojure protocols.
(defprotocol Rect
(upper-left [this])
(lower-right [this])
(area [this]))
(defn rect1 [x y width height]
(reify Rect
(upper-left [_] [x y])
(lower-right [_] [ (+ width x) (+ width y)])
(area [_] (* width height
(defn rect2 [x y width height]
(let [lr [(+ width x) (+ width y)]]
(reify Rect
(upper-left [_] [x y])
(lower-right [_] lr)
(area [_] (* width height)
On Thursday, March 5, 2015 at 4:48:11 PM UTC+1, Felix E. Klee wrote:
Disclaimer: I’ve never done *any* Clojure programming, but I’m curious.
Here’s how I may model an on-screen rectangle in JavaScript, a classless
object oriented language:
let createRectangle = function (x, y, width, height) {
return {
get upperLeft() {
return [x, y];
},
get lowerRight() {
return [x + width, y + height];
},
get area() {
return width * height;
}
};
};
let r = createRectangle(0, 0, 50, 20);
let s = createRectangle(10, 20, 40, 5);
console.log(r.upperLeft, r.lowerRight, r.area);
console.log(s.upperLeft, s.lowerRight, s.area);
Now I run the profiler. I discover that in the inner loop of my program
there are lots of calls needing the upper left and the lower right
coordinates. So I change the inner workings of the object to store these
instead:
let createRectangle = function (x, y, width, height) {
let upperLeft = [x, y], lowerRight = [x + width, y + height];
return {
get upperLeft() {
return upperLeft;
},
get lowerRight() {
return lowerRight;
},
get area() {
return (lowerRight[0] - upperLeft[0]) *
(lowerRight[1] - upperLeft[1]);
}
};
};
Boom: Now the program is twice as fast, and - what gives me great
comfort - I know that this change breaks nothing. I only had to edit the
code in *one* module. I didn’t need to think too much about efficiency
of data structures in the beginning. I could just start going, then
optimize in the end.
*Can I program in a similar way using Clojure?*
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Re: Idiomatic way to co-ordinate 'disconnected' services into a single transaction (ala Spring's @Transactional functionality)?
Hi Colin- a simple example that uses a flow operator would be
(- context
do-something
do-some-io
do-a-last-thing )
with
(defn do-something [context]
(let [some-data (get-in context [:path :to :data :element])
result (pure-edge-function some-data)]
(assoc-in context [:path :to :revised :data] result)))
and
(defn do-some-io [context]
(let [some-other-data (get-in context [:path :to :data :to :save])
database (get-in context [:path :to :database :resource])]
(save! database some-other-data)
context)))
Then save! can be a plain function, or
(defprotocol Saver
(save! [this data]))
(defrecord DatabaseSaver [conn ... ]
Saver
(save! ))
(defrecord AtomSaver [a ... ]
Saver
(save! ))
And context is a map of maps that contains both application state and edge
resources that should provide or receive data.
Encoding conditional steps in a data flow presents a challenge. Several
variants for doing this are in flow operators in Clojure and there are also
a number of third party approaches. The below is a concrete example from an
internal library that is not open source but doesn't differ significantly
from approaches that are.
A flow looks like this:
(defflow renew
{ :startvalid-request?
valid-request?{ true valid-token? false invalid-request }
valid-token? { true ingest-token false not-authorized }
ingest-token renew-session
renew-session renewed?
renewed? { true return-renewed-token false not-authorized
}
return-renewed-token :end
not-authorized :end
invalid-request:end })
It's a regular map with at least a :start key and an :end value. Symbols in
a flow map are plain functions that take a context map.
Semantically, those functions represent either actions or decisions. A
function whose value in the flow map is itself a map with true and false
keys is a decision. A function whose value in the map is another function
is an action.
This particular flow performs a renewal of a web-like session token. It
runs in a Pedestal interceptor, so it receives a context map (with
:request, :response and other keys) as a parameter and at the end it
populates the :response key of the map.
The way to read this is-
0. a context map is prepared.
1. the data flow runner looks for the :start key. the value of :start is
valid-request?
2. The value of valid-request? is a map, rather than a function, so the
flow determines valid-request? is a decision function- an ordinary function
that takes a context and is expected to return true or false.
3. the flow runner executes valid-request? If it returns true, the flow
runner proceeds to valid-token? using the same context map. If false,
proceed to invalid-request
4. valid-token? is similarly a decision function, it's executed similarly
and is also expected to return true or false. invalid-request is an action.
It's expected to return a new context map- in this case it populates the
:response with a 4xx :status and some other response attributes.
5. the flow engine keeps going between keys and values until it comes to a
value of :end. Then the resulting context is the output of the flow.
The action function in the above called renew-session can do IO to renew
a user session in the database. It's copied below.
(defn renew-session [context]
(let [database(get-in context [:components :database])
session-key (get-in context [:work :session-key])
renewed?(db/renew-session! database session-key)]
(if (not (nil? renewed?))
(assoc-in context [:work :renewed-key] session-key)
context)))
It simply pulls the database connection from the context, calls into a db
specific function, db/renew-session!, which takes a connection and a key,
and could be a protocol function that accepts a Record that encapsulates a
specific storage resource, or could be a multimethod.
This model of a data flow with actions and decisions follows Amazon's
Simple Workflow Service, and the clever encoding of that flow as a map is
due to Cognitect.
A few projects exist now that encode flows in data form with an engine to
process them. There are some trade-offs- it takes practice to read them,
you can trade off a little in performance. In the above there's a fair
amount of boilerplate that could be abstracted away along the lines of of
Prismatic's Graph.
You get a lot of other benefits- a consistent system shape, separation of
concerns between core logic and edge IO, consistent error handling,
logging/auditing, etc. Flows can be reused and can themselves compose,
because everything takes a context map. You could also generate a visual
decision tree of the model, or a real time heat map of decisions or of
action performance.
Anyway- sorry, this isn't intended to pitch an internal library, rather to
share another thought process around the problems you raised that points in
the direction of modeling and
Re: Idiomatic way to co-ordinate 'disconnected' services into a single transaction (ala Spring's @Transactional functionality)?
Thanks Jonah - I will digest this over coffee...
On 5 March 2015 at 16:45, Jonah Benton jo...@jonah.com wrote:
Hi Colin- a simple example that uses a flow operator would be
(- context
do-something
do-some-io
do-a-last-thing )
with
(defn do-something [context]
(let [some-data (get-in context [:path :to :data :element])
result (pure-edge-function some-data)]
(assoc-in context [:path :to :revised :data] result)))
and
(defn do-some-io [context]
(let [some-other-data (get-in context [:path :to :data :to :save])
database (get-in context [:path :to :database :resource])]
(save! database some-other-data)
context)))
Then save! can be a plain function, or
(defprotocol Saver
(save! [this data]))
(defrecord DatabaseSaver [conn ... ]
Saver
(save! ))
(defrecord AtomSaver [a ... ]
Saver
(save! ))
And context is a map of maps that contains both application state and edge
resources that should provide or receive data.
Encoding conditional steps in a data flow presents a challenge. Several
variants for doing this are in flow operators in Clojure and there are also
a number of third party approaches. The below is a concrete example from an
internal library that is not open source but doesn't differ significantly
from approaches that are.
A flow looks like this:
(defflow renew
{ :startvalid-request?
valid-request?{ true valid-token? false invalid-request }
valid-token? { true ingest-token false not-authorized }
ingest-token renew-session
renew-session renewed?
renewed? { true return-renewed-token false not-authorized
}
return-renewed-token :end
not-authorized :end
invalid-request:end })
It's a regular map with at least a :start key and an :end value. Symbols in
a flow map are plain functions that take a context map.
Semantically, those functions represent either actions or decisions. A
function whose value in the flow map is itself a map with true and false
keys is a decision. A function whose value in the map is another function is
an action.
This particular flow performs a renewal of a web-like session token. It
runs in a Pedestal interceptor, so it receives a context map (with :request,
:response and other keys) as a parameter and at the end it populates the
:response key of the map.
The way to read this is-
0. a context map is prepared.
1. the data flow runner looks for the :start key. the value of :start is
valid-request?
2. The value of valid-request? is a map, rather than a function, so the flow
determines valid-request? is a decision function- an ordinary function that
takes a context and is expected to return true or false.
3. the flow runner executes valid-request? If it returns true, the flow
runner proceeds to valid-token? using the same context map. If false,
proceed to invalid-request
4. valid-token? is similarly a decision function, it's executed similarly
and is also expected to return true or false. invalid-request is an action.
It's expected to return a new context map- in this case it populates the
:response with a 4xx :status and some other response attributes.
5. the flow engine keeps going between keys and values until it comes to a
value of :end. Then the resulting context is the output of the flow.
The action function in the above called renew-session can do IO to renew a
user session in the database. It's copied below.
(defn renew-session [context]
(let [database(get-in context [:components :database])
session-key (get-in context [:work :session-key])
renewed?(db/renew-session! database session-key)]
(if (not (nil? renewed?))
(assoc-in context [:work :renewed-key] session-key)
context)))
It simply pulls the database connection from the context, calls into a db
specific function, db/renew-session!, which takes a connection and a key,
and could be a protocol function that accepts a Record that encapsulates a
specific storage resource, or could be a multimethod.
This model of a data flow with actions and decisions follows Amazon's Simple
Workflow Service, and the clever encoding of that flow as a map is due to
Cognitect.
A few projects exist now that encode flows in data form with an engine to
process them. There are some trade-offs- it takes practice to read them, you
can trade off a little in performance. In the above there's a fair amount of
boilerplate that could be abstracted away along the lines of of Prismatic's
Graph.
You get a lot of other benefits- a consistent system shape, separation of
concerns between core logic and edge IO, consistent error handling,
logging/auditing, etc. Flows can be reused and can themselves compose,
because everything takes a context map. You could also generate a visual
decision tree of the model, or a real time heat map of decisions
Re: partition-when
For the transducer version, I don’t think you need to keep track of the
previous value (fval). The decision to start a new partition group depends only
on the current item. Here’s my version. (Warning: virtually untested.) I
assume that the first item goes into the first partition no matter what so you
don’t even need to call f. Maybe you should for side-effects?
(defn partition-when
Applies f to each value in coll, starting a new partition each time f
returns a
true value. Returns a lazy seq of partitions. Returns a stateful
transducer when no collection is provided.
{:added 1.X
:static true}
([f]
(fn [rf]
(let [a (java.util.ArrayList.)]
(fn
([] (rf))
([result]
(let [result (if (.isEmpty a)
result
(let [v (vec (.toArray a))]
;;clear first!
(.clear a)
(unreduced (rf result v]
(rf result)))
([result input]
(if (.isEmpty a)
(do (.add a input)
result)
(if (f input)
(let [v (vec (.toArray a))]
(.clear a)
(let [ret (rf result v)]
(when-not (reduced? ret)
(.add a input))
ret))
(do
(.add a input)
result
([f coll]
(lazy-seq
(when-let [s (seq coll)]
(let [fst (first s)
run (cons fst (take-while #(not (f %)) (next s)))]
(cons run (partition-when f (seq (drop (count run) s)
— Steve
On Mar 5, 2015, at 12:11 PM, Andy- andre.r...@gmail.com wrote:
Tried myself and my first transducer for fun:
(defn partition-when
[f]
(fn [rf]
(let [a (java.util.ArrayList.)
fval (volatile! false)]
(fn
([] (rf))
([result]
(let [result (if (.isEmpty a)
result
(let [v (vec (.toArray a))]
;;clear first!
(.clear a)
(unreduced (rf result v]
(rf result)))
([result input]
(if-not (and (f input) @fval)
(do
(vreset! fval true)
(.add a input)
result)
(let [v (vec (.toArray a))]
(.clear a)
(let [ret (rf result v)]
(when-not (reduced? ret)
(.add a input))
ret
(into [] (partition-when
#(.startsWith % ))
[ 1 2 22 3])
Based on partition-by (on master branch). Would be interesting how fast it is
compared to the other implementations.
Any comments appreciated.
Cheers
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Re: clojure map to java instance of pojo class
thanks, i test with defrecord.
On Thursday, March 5, 2015 at 4:39:03 PM UTC+8, Colin Yates wrote:
Isn't this exactly what defrecord does?
On 5 March 2015 at 07:42, Xiangtao Zhou tao...@gmail.com javascript:
wrote:
hi all,
is there some library or simple way to do it like the function
map-to-pojo
in the following code ?
java code
class A{
public int a;
public String b;
}
clojure code
(def a {:a 1 :b 2})
(def b (map-to-pojo a A))
(instance? b A)
any solution is good.
Joe
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Re: clojure map to java instance of pojo class
Isn't this exactly what defrecord does?
On 5 March 2015 at 07:42, Xiangtao Zhou tao...@gmail.com wrote:
hi all,
is there some library or simple way to do it like the function map-to-pojo
in the following code ?
java code
class A{
public int a;
public String b;
}
clojure code
(def a {:a 1 :b 2})
(def b (map-to-pojo a A))
(instance? b A)
any solution is good.
Joe
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Re: partition-when
Tried myself and my first transducer for fun: (defn partition-when [f] (fn [rf] (let [a (java.util.ArrayList.) fval (volatile! false)] (fn ([] (rf)) ([result] (let [result (if (.isEmpty a) result (let [v (vec (.toArray a))] ;;clear first! (.clear a) (unreduced (rf result v] (rf result))) ([result input] (if-not (and (f input) @fval) (do (vreset! fval true) (.add a input) result) (let [v (vec (.toArray a))] (.clear a) (let [ret (rf result v)] (when-not (reduced? ret) (.add a input)) ret (into [] (partition-when #(.startsWith % )) [ 1 2 22 3]) Based on partition-by (on master branch). Would be interesting how fast it is compared to the other implementations. Any comments appreciated. Cheers On Tuesday, March 3, 2015 at 2:46:29 PM UTC-5, Frank wrote: Hi all, for some tests I need a function which starts a new partition each time a predicate returns true, for instance: (partition-when (fn [s] (.startsWith s )) [ 1 2 3 4 5 6]) := [[ 1 2 3] [ 4 5 6]] Since I haven't found a built-in function, I copied, pasted, and modified the core function partition-by: (defn partition-when [f coll] (lazy-seq (when-let [s (seq coll)] (let [fst (first s) run (cons fst (take-while #(not (f %)) (next s)))] (cons run (partition-when f (seq (drop (count run) s Is there a better (more idiomatic) way to achieve the same result? Thank you in advance. Frank -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: Any Lispers in South Devon, UK?
Hi Stephen Just seconding John Kane's post below - there are a few of us (including John and Dan Stone) who met up at the Exeter Web session last week. I'd definitely be interested in meeting up if something in Exeter works for you. Martin -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: Idiomatic way to co-ordinate 'disconnected' services into a single transaction (ala Spring's @Transactional functionality)?
Hi Jonah,
This sounds very much like the model layer in DDD, which ironically is
exactly what I am building.
However, in the middle of a data flow a function needs to reach out to
a repository to make a decision - how does that fit in with the data
flow approach?
On 5 March 2015 at 13:39, Jonah Benton jo...@jonah.com wrote:
Hi Colin,
Another option, other than HOFs or dynamic binding, is what might be called
a data flow approach.
At the edge of the application are the functions that explicitly take
parameterized resources to perform edge state IO. These might be bare
functions, or they might be protocol implementations that await the delivery
of a type to perform their operation, or multimethods.
At the center are functions that take a context map, which contains all
relevant application state- IO resources and transient state data. Those
functions are arranged in a data flow and capture the logic or state
transitions of the application independent of any specific IO commitments.
They can use schema or type annotation or pre/post conditions to enforce
invariants.
When data flow processing arrives at a place where some edge IO should
occur, these data flow functions act as adapters to get-in the appropriate
resource or Record from the context map and call the edge functions to
perform IO.
The result is a wider, flatter system, propagating state explicitly rather
than implicitly through the call stack.
Jonah
On Wed, Mar 4, 2015 at 12:58 PM, Colin Yates colin.ya...@gmail.com wrote:
Hi,
I am looking for the Clojure equivalent of:
class Whatever {
@Transactional
void doSomething(IDoSomething one, IDoSomethingElse two) {
one.doSomething()
two.doSomething()
}
}
where both one and two are dependency injected with a proxy which resolves
to a thread local database connection. In addition, one might itself have a
collaborator which itself has a collaborator which needs a datasource.
So far I have two protocols:
(defprotocol IDoSomething
(do-something [this ...])
(defprotocol IDoSomethingElse
(do-something [this ...])
Each protocol may have a number of implementations, one of which is a JDBC
implementation:
(defrecord JdbcIDoSomething [db]
(do-something [this ...] ...))
The problem is that the calling code only gets provided an IDoSomething
and an IDoSomethingElse and it wants to do something like:
(let [one (-JdbcDoSomething db) two (-JdbcDoSomethingElse db)]
(with-transaction [tx db]
(do-something one)
(do-something-else two)))
The problem here is that the implementations of do-something and
do-something-else won't have access to the local bound 'tx', they will have
their own 'db'.
I realise the general argument is to be explicit and pass a db as the
first argument to the protocol but this isn't appropriate in this case as
there are validly multiple implementations. I could abstract a
'unit-of-work' and pass that as the first argument to the protocols but that
seems a bit painful.
Also, these protocols may be used quite far away from where the database
code lives and passing a parameter all the way through the call stack is
painful.
I am using Stuart Sierra's components if that makes any difference.
I can't be the first person to run into this but google is surprisingly
unhelpful which makes me think I have missed something fundamental, and that
I have something upside down.
What do you all do?
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Re: Any Lispers in South Devon, UK?
There are also a few of us in the Southampton/Winchester area Get in touch if you are interested. Thomas On Tuesday, 3 March 2015 21:53:57 UTC, Stephen Wakely wrote: Hi, Are there any other Lispers in South Devon who would be interested in meeting up and talking code? Clojure, Common Lisp, Scheme, anything as long as there are loads of parentheses! Please get in touch. Cheers Stephen -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: Idiomatic way to co-ordinate 'disconnected' services into a single transaction (ala Spring's @Transactional functionality)?
Yes, exactly.
That's fine, a node in the middle of the data flow can be responsible for
reaching out to the edge to synchronously get some data to feed into a
decision performed by the data flow. It would just do that through the edge
functions.
A request for data could also be asynchronously initiated once enough
context had been determined by the data flow, and a promise added to the
context map for later derefing (likely with a timeout).
If the request for the data is context-free, it could be pulled in at the
start of the data flow.
By edge, it's is not that IO can't be done in the middle of a dataflow,
it's just that functions that deal with dataflow follow one pattern (taking
a context map) so they can be easily composed and rearranged, while
functions that deal with edge resources take those resources along with
other parameters more explicitly, so the data flow can run in an insulated
fashion.
On Thu, Mar 5, 2015 at 8:55 AM, Colin Yates colin.ya...@gmail.com wrote:
Hi Jonah,
This sounds very much like the model layer in DDD, which ironically is
exactly what I am building.
However, in the middle of a data flow a function needs to reach out to
a repository to make a decision - how does that fit in with the data
flow approach?
On 5 March 2015 at 13:39, Jonah Benton jo...@jonah.com wrote:
Hi Colin,
Another option, other than HOFs or dynamic binding, is what might be
called
a data flow approach.
At the edge of the application are the functions that explicitly take
parameterized resources to perform edge state IO. These might be bare
functions, or they might be protocol implementations that await the
delivery
of a type to perform their operation, or multimethods.
At the center are functions that take a context map, which contains all
relevant application state- IO resources and transient state data. Those
functions are arranged in a data flow and capture the logic or state
transitions of the application independent of any specific IO
commitments.
They can use schema or type annotation or pre/post conditions to enforce
invariants.
When data flow processing arrives at a place where some edge IO should
occur, these data flow functions act as adapters to get-in the
appropriate
resource or Record from the context map and call the edge functions to
perform IO.
The result is a wider, flatter system, propagating state explicitly
rather
than implicitly through the call stack.
Jonah
On Wed, Mar 4, 2015 at 12:58 PM, Colin Yates colin.ya...@gmail.com
wrote:
Hi,
I am looking for the Clojure equivalent of:
class Whatever {
@Transactional
void doSomething(IDoSomething one, IDoSomethingElse two) {
one.doSomething()
two.doSomething()
}
}
where both one and two are dependency injected with a proxy which
resolves
to a thread local database connection. In addition, one might itself
have a
collaborator which itself has a collaborator which needs a datasource.
So far I have two protocols:
(defprotocol IDoSomething
(do-something [this ...])
(defprotocol IDoSomethingElse
(do-something [this ...])
Each protocol may have a number of implementations, one of which is a
JDBC
implementation:
(defrecord JdbcIDoSomething [db]
(do-something [this ...] ...))
The problem is that the calling code only gets provided an IDoSomething
and an IDoSomethingElse and it wants to do something like:
(let [one (-JdbcDoSomething db) two (-JdbcDoSomethingElse db)]
(with-transaction [tx db]
(do-something one)
(do-something-else two)))
The problem here is that the implementations of do-something and
do-something-else won't have access to the local bound 'tx', they will
have
their own 'db'.
I realise the general argument is to be explicit and pass a db as the
first argument to the protocol but this isn't appropriate in this case
as
there are validly multiple implementations. I could abstract a
'unit-of-work' and pass that as the first argument to the protocols but
that
seems a bit painful.
Also, these protocols may be used quite far away from where the database
code lives and passing a parameter all the way through the call stack is
painful.
I am using Stuart Sierra's components if that makes any difference.
I can't be the first person to run into this but google is surprisingly
unhelpful which makes me think I have missed something fundamental, and
that
I have something upside down.
What do you all do?
--
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Re: Who's using Clojure?
I'm about to start training 4 devs on my team at Oracle in Clojure. My manager is very nervous about putting Clojure into the product. I'm forging on regardless :) I rewrote some components of our product in Clojure in my spare time, mainly as a proof of concept that we could do some of our analytics in the streaming model rather than in the data warehousing model. As sometimes happens, the POC was so simple and fast that the team is now interested in productizing it. In our last 1-1 meeting, my manager told me he had searched LinkedIn for Clojure and only got 9000 matches. Whereas his search for Java turned up 80 million or some such. My rebuttal is that those are the 9000 smartest developers, so you should be trying to recruit them. --mike On Tuesday, April 19, 2011 at 7:38:14 AM UTC-7, Damien wrote: Hi Everyone, I'm on a mission: introducing Clojure in my company, which is a big consulting company like many others. I started talking about Clojure to my manager yesterday. I was prepared to talk about all the technical benefits and he was interested. I still have a long way to go but I think that was a good start. However I need to figure out how to answer to one of his questions: who is using Clojure? Obviously I know each of you is using Clojure, that makes almost 5,000 people. I know there is Relevance and Clojure/core. I read about BackType or FlightCaster using Clojure. But, let's face it, that doesn't give me a killer answer. What could help is a list of success stories, a bit like MongoDB published here: http://www.mongodb.org/display/DOCS/Production+Deployments Is there a place where I could find this kind of information for Clojure? Thanks -- Damien Lepage http://damienlepage.com -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: partition-when
Hi Frank, I use a similar function that combines partition-by and partition-all: (defn partition-when [f coll] (map (partial apply concat) (partition-all 2 (partition-by f coll Martin. On Wed, Mar 4, 2015 at 10:19 PM, Ivan L ivan.laza...@gmail.com wrote: I went though almost the exact same exercise and my code is almost identical to yours. I called it partition-every and I use it a lot. A more determined individual might submit this for inclusion into core! On Tuesday, March 3, 2015 at 2:46:29 PM UTC-5, Frank wrote: Hi all, for some tests I need a function which starts a new partition each time a predicate returns true, for instance: (partition-when (fn [s] (.startsWith s )) [ 1 2 3 4 5 6]) := [[ 1 2 3] [ 4 5 6]] Since I haven't found a built-in function, I copied, pasted, and modified the core function partition-by: (defn partition-when [f coll] (lazy-seq (when-let [s (seq coll)] (let [fst (first s) run (cons fst (take-while #(not (f %)) (next s)))] (cons run (partition-when f (seq (drop (count run) s Is there a better (more idiomatic) way to achieve the same result? Thank you in advance. Frank -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: Idiomatic way to co-ordinate 'disconnected' services into a single transaction (ala Spring's @Transactional functionality)?
Sounds interesting - are there are instances that I can look at?
On 5 March 2015 at 14:15, Jonah Benton jo...@jonah.com wrote:
Yes, exactly.
That's fine, a node in the middle of the data flow can be responsible for
reaching out to the edge to synchronously get some data to feed into a
decision performed by the data flow. It would just do that through the edge
functions.
A request for data could also be asynchronously initiated once enough
context had been determined by the data flow, and a promise added to the
context map for later derefing (likely with a timeout).
If the request for the data is context-free, it could be pulled in at the
start of the data flow.
By edge, it's is not that IO can't be done in the middle of a dataflow, it's
just that functions that deal with dataflow follow one pattern (taking a
context map) so they can be easily composed and rearranged, while functions
that deal with edge resources take those resources along with other
parameters more explicitly, so the data flow can run in an insulated
fashion.
On Thu, Mar 5, 2015 at 8:55 AM, Colin Yates colin.ya...@gmail.com wrote:
Hi Jonah,
This sounds very much like the model layer in DDD, which ironically is
exactly what I am building.
However, in the middle of a data flow a function needs to reach out to
a repository to make a decision - how does that fit in with the data
flow approach?
On 5 March 2015 at 13:39, Jonah Benton jo...@jonah.com wrote:
Hi Colin,
Another option, other than HOFs or dynamic binding, is what might be
called
a data flow approach.
At the edge of the application are the functions that explicitly take
parameterized resources to perform edge state IO. These might be bare
functions, or they might be protocol implementations that await the
delivery
of a type to perform their operation, or multimethods.
At the center are functions that take a context map, which contains all
relevant application state- IO resources and transient state data. Those
functions are arranged in a data flow and capture the logic or state
transitions of the application independent of any specific IO
commitments.
They can use schema or type annotation or pre/post conditions to enforce
invariants.
When data flow processing arrives at a place where some edge IO should
occur, these data flow functions act as adapters to get-in the
appropriate
resource or Record from the context map and call the edge functions to
perform IO.
The result is a wider, flatter system, propagating state explicitly
rather
than implicitly through the call stack.
Jonah
On Wed, Mar 4, 2015 at 12:58 PM, Colin Yates colin.ya...@gmail.com
wrote:
Hi,
I am looking for the Clojure equivalent of:
class Whatever {
@Transactional
void doSomething(IDoSomething one, IDoSomethingElse two) {
one.doSomething()
two.doSomething()
}
}
where both one and two are dependency injected with a proxy which
resolves
to a thread local database connection. In addition, one might itself
have a
collaborator which itself has a collaborator which needs a datasource.
So far I have two protocols:
(defprotocol IDoSomething
(do-something [this ...])
(defprotocol IDoSomethingElse
(do-something [this ...])
Each protocol may have a number of implementations, one of which is a
JDBC
implementation:
(defrecord JdbcIDoSomething [db]
(do-something [this ...] ...))
The problem is that the calling code only gets provided an IDoSomething
and an IDoSomethingElse and it wants to do something like:
(let [one (-JdbcDoSomething db) two (-JdbcDoSomethingElse db)]
(with-transaction [tx db]
(do-something one)
(do-something-else two)))
The problem here is that the implementations of do-something and
do-something-else won't have access to the local bound 'tx', they will
have
their own 'db'.
I realise the general argument is to be explicit and pass a db as the
first argument to the protocol but this isn't appropriate in this case
as
there are validly multiple implementations. I could abstract a
'unit-of-work' and pass that as the first argument to the protocols but
that
seems a bit painful.
Also, these protocols may be used quite far away from where the
database
code lives and passing a parameter all the way through the call stack
is
painful.
I am using Stuart Sierra's components if that makes any difference.
I can't be the first person to run into this but google is surprisingly
unhelpful which makes me think I have missed something fundamental, and
that
I have something upside down.
What do you all do?
--
You received this message because you are subscribed to the Google
Groups Clojure group.
To post to this group, send email to clojure@googlegroups.com
Note that posts from new members are moderated - please be patient with
your first
Re: Any Lispers in South Devon, UK?
On 5 March 2015 at 14:08, Thomas th.vanderv...@gmail.com wrote: There are also a few of us in the Southampton/Winchester area Get in touch if you are interested. I am in Southampton and would be interested in meeting some Clojurians. Alan -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [ANN] Understanding the Persistent Vector
This was fantastic. Really looking forward to the RRB Tree. On Wednesday, March 4, 2015 at 12:31:54 PM UTC-5, Jean Niklas L'orange wrote: Hi Frank, On Wednesday, March 4, 2015 at 12:24:42 PM UTC+1, Frank Castellucci wrote: Will you be doing this for other data types? I will have a small break first, but I intend to do the same kind of series for persistent hash maps/sets. Maybe even RRB-trees if people are interested (I found them to be pretty hard to grasp by the paper alone). Again, Great Work! Thanks! =) -- Jean Niklas Frank On Saturday, February 28, 2015 at 11:14:17 AM UTC-5, Jean Niklas L'orange wrote: Hello fellow Clojurians, I am happy to announce that I have finished my blogpost series on the persistent vector. It consists of five parts: 1. The basic algorithms http://hypirion.com/musings/understanding-persistent-vector-pt-1 2. Indexing http://hypirion.com/musings/understanding-persistent-vector-pt-2 3. The tail optimisation http://hypirion.com/musings/understanding-persistent-vector-pt-3 4. Transients http://hypirion.com/musings/understanding-clojure-transients 5. Performance http://hypirion.com/musings/persistent-vector-performance-summarised (which is a summary of this detailed blogpost http://hypirion.com/musings/persistent-vector-performance) I hope this will help you to get a good understanding of how the algorithms on the data structure work, how the optimisations work, and how efficient it is on the JVM. Constructive criticism, both positive and negative, is appreciated. Enjoy! (NB: I haven't gotten around to fix the illustrations in part 3, so unfortunately it will be a bit hard to read if you print it out in grayscale. It's on my todo-list.) -- Jean Niklas L'orange -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: Idiomatic way to co-ordinate 'disconnected' services into a single transaction (ala Spring's @Transactional functionality)?
Hi Colin,
Another option, other than HOFs or dynamic binding, is what might be called
a data flow approach.
At the edge of the application are the functions that explicitly take
parameterized resources to perform edge state IO. These might be bare
functions, or they might be protocol implementations that await the
delivery of a type to perform their operation, or multimethods.
At the center are functions that take a context map, which contains all
relevant application state- IO resources and transient state data. Those
functions are arranged in a data flow and capture the logic or state
transitions of the application independent of any specific IO commitments.
They can use schema or type annotation or pre/post conditions to enforce
invariants.
When data flow processing arrives at a place where some edge IO should
occur, these data flow functions act as adapters to get-in the appropriate
resource or Record from the context map and call the edge functions to
perform IO.
The result is a wider, flatter system, propagating state explicitly rather
than implicitly through the call stack.
Jonah
On Wed, Mar 4, 2015 at 12:58 PM, Colin Yates colin.ya...@gmail.com wrote:
Hi,
I am looking for the Clojure equivalent of:
class Whatever {
@Transactional
void doSomething(IDoSomething one, IDoSomethingElse two) {
one.doSomething()
two.doSomething()
}
}
where both one and two are dependency injected with a proxy which resolves
to a thread local database connection. In addition, one might itself have a
collaborator which itself has a collaborator which needs a datasource.
So far I have two protocols:
(defprotocol IDoSomething
(do-something [this ...])
(defprotocol IDoSomethingElse
(do-something [this ...])
Each protocol may have a number of implementations, one of which is a JDBC
implementation:
(defrecord JdbcIDoSomething [db]
(do-something [this ...] ...))
The problem is that the calling code only gets provided an IDoSomething
and an IDoSomethingElse and it wants to do something like:
(let [one (-JdbcDoSomething db) two (-JdbcDoSomethingElse db)]
(with-transaction [tx db]
(do-something one)
(do-something-else two)))
The problem here is that the implementations of do-something and
do-something-else won't have access to the local bound 'tx', they will have
their own 'db'.
I realise the general argument is to be explicit and pass a db as the
first argument to the protocol but this isn't appropriate in this case as
there are validly multiple implementations. I could abstract a
'unit-of-work' and pass that as the first argument to the protocols but
that seems a bit painful.
Also, these protocols may be used quite far away from where the database
code lives and passing a parameter all the way through the call stack is
painful.
I am using Stuart Sierra's components if that makes any difference.
I can't be the first person to run into this but google is surprisingly
unhelpful which makes me think I have missed something fundamental, and
that I have something upside down.
What do you all do?
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Re: Om design query
One workable possibility: * init a core.async channel in the container * pass the channel from the container into each child component at build time using :opts or :state * send the discovered size of each child component, with identifying data, as a channel message during IDidMount I don't find these sorts of solutions terribly elegant but it would be usable I think. Tom On Friday, 6 March 2015 12:42:12 UTC+8, James Reeves wrote: I've been writing an application using Om, and I've come across a problem I haven't been able to find a good solution for. I'd be grateful for any ideas people might have on how to proceed. In a nutshell, I have a bunch of elements that need to be arranged according to a specific algorithm. They cannot overlap, so I need to know the sizes of all the elements in order to arrange them. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [ANN] Dunaj project, an alternative core API for Clojure
Ivan was probably talking about dunaj-starter repo on github: https://github.com/dunaj-project/dunaj-starter/blob/master/src/dunaj_starter/core.clj пятница, 6 марта 2015 г., 9:42:00 UTC+3 пользователь Alex Baranosky написал: Where is this example project? On Thu, Mar 5, 2015 at 7:40 PM, Ivan L ivan.l...@gmail.com javascript: wrote: Just a quick glance at the example project shows integrated type definitions. I'm curious for sure. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clo...@googlegroups.com javascript: Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+u...@googlegroups.com javascript: For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+u...@googlegroups.com javascript:. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Om design query
I've been writing an application using Om, and I've come across a problem I haven't been able to find a good solution for. I'd be grateful for any ideas people might have on how to proceed. In a nutshell, I have a bunch of elements that need to be arranged according to a specific algorithm. They cannot overlap, so I need to know the sizes of all the elements in order to arrange them. Om has an IDidMount protocol which is called after the component has been mounted into the DOM. I can use this to find out the size of the element: (let [node (get-node owner)] [(.-offsetWidth node) (.-offsetHeight node)]) Elements can be hidden with visibility: hidden until their sizes are known. The problem that's stumping me is how to deliver the sizes back to the containing component so that all the elements can be arranged correctly. The most obvious way is via the cursor, but I don't like the idea of mixing application state with local display information. Can anyone think of a better way? - James -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: Om design query
(cc'ing clojurescr...@googlegroups.com) Hi James, Let me make sure I understand what you're asking: you have a parent enclosing component that has to do calculations to position a set of child component element, but you can only properly calculate positioning for those child elements (in the parent?) after you get offset position information for each one, once they have mounted? DD On 2015/03/06 13:40, James Reeves wrote: I've been writing an application using Om, and I've come across a problem I haven't been able to find a good solution for. I'd be grateful for any ideas people might have on how to proceed. In a nutshell, I have a bunch of elements that need to be arranged according to a specific algorithm. They cannot overlap, so I need to know the sizes of all the elements in order to arrange them. Om has an IDidMount protocol which is called after the component has been mounted into the DOM. I can use this to find out the size of the element: (let [node (get-node owner)] [(.-offsetWidth node) (.-offsetHeight node)]) Elements can be hidden with visibility: hidden until their sizes are known. The problem that's stumping me is how to deliver the sizes back to the containing component so that all the elements can be arranged correctly. The most obvious way is via the cursor, but I don't like the idea of mixing application state with local display information. Can anyone think of a better way? - James -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com mailto:clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
