Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations about Factor
Maybe the dsl aspect could be viewed as applying a layer of sugar to the stack based workhorse. Somewhat, but it is much more than sugar. It is grease for the mind and ironically traction too. Shuffling is fragile until you are fluent. Even then it is work, and causes mistakes. It is not a load I want to carry at my DSL level. I'll endure it as I must at the bottom, but I don't want to work at the bottom when I'm immersed in thoughts of domain X. You could easily have 'adjectives' that accumulate into a variable, Yes. I have a noun-phrase grammar that uses mostly past participles (one kind of adjective called a verbal) and adjectives proper as mutative (the U in CRUD) and creative (the C in CRUD) modifiers. We need a tree for this. Free-form text, after three decades, looks silly. not on the stack, then a noun word that takes those options and does the work. The noun (if it is a class) is instantiated or (if it is an instance) consumed or mutated. In any of these cases, you have a noun phrase. This is how I accumulate attributes for the HTML elements, and it feels like a dsl: "Save" button <>submit "org" id <>form +content button puts save into an attribute variable <>submit uses (and clears) that variable, appends to the working collection id puts "org" in the same place that button put things before <>form uses the all-id variable to set attributes as it wraps what's on the stack +content puts it away somewhere. This, I think, works fine for a dsl. It also works fine if the 'attribute value' is a field of an object on the stack, and the stack throughout this is ( page-assembly current-chunk xx -- page-assembly current-chunk ) or sometimes going down to ( page-assembly current-chunk -- page-assembly ) Using vocabularies, you could even keep an internal and an external version of the word, where the stack one works faster, the other is the DSL. I need to be more familiar with all of the concepts and terms involved, to produce a minimal set of well-factors nouns and modifiers. Do you have a complete example of a page creation-and-exercise scenario, against a Factor-hosted web-server? That would provide plenty of context. The page created/served/submitted can be small, like that form you showed me the other day. Shaping -- The Next 800 Companies to Lead America's Growth: New Video Whitepaper David G. Thomson, author of the best-selling book "Blueprint to a Billion" shares his insights and actions to help propel your business during the next growth cycle. Listen Now! http://p.sf.net/sfu/SAP-dev2dev___ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk
Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations about Factor
Thanks for that Joe. That helps a lot. If I want general-to-particular reading order, must I define a parsing word of my own? Stack efficient order: b negated 1/2a * :> -b/2a Context efficient order (general-to-particular perception and reasoning): -b/2a <: b negated a/2 * (Yes, I made up my own long forms of recip, neg, and sq. ) That last form is like a traditional assignment statement. How then do I write the definition for <: ? Shaping From: Joe Groff [mailto:arc...@gmail.com] Sent: 2010-November-09, 21:38 To: factor-talk@lists.sourceforge.net Subject: Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations about Factor On Nov 9, 2010, at 2:08 PM, Shaping wrote: I'm hungry for local variables, now, though this goes against much of the basis of stack languages. I want lexical forms I can read and understand (parse with my mind, left-to-right, and down in a tree) to produce a known result (not a best guess). I don't want to remember a lot of stuff, because human memory is fragile and ultimately limits all programmers. I know that we have a "locals" vocab of some kind, but don't know how to use it. Is anyone using locals a lot in Factor just for readability? Can locals be used efficiently for the machine, too? How can locals be abused? Locals are used all over the place, and suffer no performance penalty. Don't worry about using them, or "going against the basis of stack languages." Practicality beats purity. Often, after writing something out with locals, it makes the concatenative approach clearer. You can bind local variables by using the "::" definition form, which binds the function's input values to lexical variables: :: add ( x y -- z ) x y + ; Within a :: definition, you can bind additional variables off the top of the stack with the ":>" operator: :: quadratic ( a b c -- x1 x2 ) 2 a * recip :> 1/2a b neg 1/2a * :> -b/2a b sq 4 a c * * - sqrt 1/2a * :> disc/2a -b/2a disc/2a + -b/2a disc/2a - ; -Joe -- The Next 800 Companies to Lead America's Growth: New Video Whitepaper David G. Thomson, author of the best-selling book "Blueprint to a Billion" shares his insights and actions to help propel your business during the next growth cycle. Listen Now! http://p.sf.net/sfu/SAP-dev2dev___ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk
Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations about Factor
On Wed, Nov 10, 2010 at 4:51 PM, Shaping wrote: > If I want general-to-particular reading order, must I define a parsing word > of my own? > > -b/2a <: b negated a/2 * Defining a <: operator with that exact syntax is not possible. For one, in Factor, new symbol names can only be created as part of syntax forms, and so must come after a syntax word of some sort. The new name "-b/2a" in this case comes before the <: syntax word. The other problem is that you need some way to indicate where the expression whose value is being bound ends. You could, however, define a form with explicit opening and closing tokens, for example: [set -b/2a := b negated a/2 * ] The definition for "[set" would look something like this: -- SYNTAX: [set scan locals get parse-def ! scan a token and parse it as a locals binding ":=" expect ! scan a token and raise an error if it's not ":=" \ ] parse-until ! scan and parse objects until the "]" word is parsed swap suffix! append! ; ! append first the expression body, then the local definition to the parser accumulator ! as if it had appeared as "expression :> name" :: foo ( x y -- z ) [set z := x y + ] z ; -- -Joe -- The Next 800 Companies to Lead America's Growth: New Video Whitepaper David G. Thomson, author of the best-selling book "Blueprint to a Billion" shares his insights and actions to help propel your business during the next growth cycle. Listen Now! http://p.sf.net/sfu/SAP-dev2dev ___ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk
Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations about Factor
On Nov 9, 2010, at 2:08 PM, Shaping wrote: > > I'm hungry for local variables, now, though this goes against much of the > basis of stack languages. I want lexical forms I can read and understand > (parse with my mind, left-to-right, and down in a tree) to produce a known > result (not a best guess). I don't want to remember a lot of stuff, because > human memory is fragile and ultimately limits all programmers. I know that > we have a "locals" vocab of some kind, but don't know how to use it. Is > anyone using locals a lot in Factor just for readability? Can locals be used > efficiently for the machine, too? How can locals be abused? Locals are used all over the place, and suffer no performance penalty. Don't worry about using them, or "going against the basis of stack languages." Practicality beats purity. Often, after writing something out with locals, it makes the concatenative approach clearer. You can bind local variables by using the "::" definition form, which binds the function's input values to lexical variables: :: add ( x y -- z ) x y + ; Within a :: definition, you can bind additional variables off the top of the stack with the ":>" operator: :: quadratic ( a b c -- x1 x2 ) 2 a * recip :> 1/2a b neg 1/2a * :> -b/2a b sq 4 a c * * - sqrt 1/2a * :> disc/2a -b/2a disc/2a + -b/2a disc/2a - ; -Joe -- The Next 800 Companies to Lead America's Growth: New Video Whitepaper David G. Thomson, author of the best-selling book "Blueprint to a Billion" shares his insights and actions to help propel your business during the next growth cycle. Listen Now! http://p.sf.net/sfu/SAP-dev2dev___ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk
Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations about Factor
Maybe the dsl aspect could be viewed as applying a layer of sugar to the stack based workhorse. You could easily have 'adjectives' that accumulate into a variable, not on the stack, then a noun word that takes those options and does the work. This is how I accumulate attributes for the HTML elements, and it feels like a dsl: "Save" button <>submit "org" id <>form +content button puts save into an attribute variable <>submit uses (and clears) that variable, appends to the working collection id puts "org" in the same place that button put things before <>form uses the all-id variable to set attributes as it wraps what's on the stack +content puts it away somewhere. This, I think, works fine for a dsl. It also works fine if the 'attribute value' is a field of an object on the stack, and the stack throughout this is ( page-assembly current-chunk xx -- page-assembly current-chunk ) or sometimes going down to ( page-assembly current-chunk -- page-assembly ) Using vocabularies, you could even keep an internal and an external version of the word, where the stack one works faster, the other is the DSL. -- The Next 800 Companies to Lead America's Growth: New Video Whitepaper David G. Thomson, author of the best-selling book "Blueprint to a Billion" shares his insights and actions to help propel your business during the next growth cycle. Listen Now! http://p.sf.net/sfu/SAP-dev2dev___ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk
Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations about Factor
Shaping, have you read this page : http://concatenative.org/wiki/view/Concatenative%20language ? Jon On Tue, Nov 9, 2010 at 10:44 AM, Shaping wrote: > Thanks Chris. I'm working on this now. > > I managed to get the Browser looking really good with the stylesheet tweak > that kenanb suggested. Does anyone know how to change the font style and > size in the Listener. > > Shaping > > > -Original Message- > From: Chris Double [mailto:chris.dou...@double.co.nz] > Sent: 2010-November-09, 02:57 > To: factor-talk@lists.sourceforge.net > Subject: Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations > about Factor > > On Tue, Nov 9, 2010 at 9:38 PM, Shaping wrote: >> I need to be able to write a parser in a >> straightforward way (XStreams-style maybe) using a PEG (collection of BNF >> productions) so that I can experiment efficiently with this idea. Does >> anyone have any experience with PEGs in Factor? > > Read the help for peg.ebnf. You can do this with the following in the > listener: > > "peg.ebnf" about > > Also these blog posts: > > http://www.bluishcoder.co.nz/2007/11/embedded-grammars-in-factor.html > http://www.bluishcoder.co.nz/2008/04/factor-parsing-dsl.html > http://www.bluishcoder.co.nz/2008/06/parsing-javascript-with-factor.html > > The code in them is slightly out of date but combined with the > peg.ebnf help you should be able to get the idea. There are a few > peg.ebnf usage examples for a JavaScript grammar, a PL0 grammar and an > expression calculator in the Factor source. > > My PDF of articles might have more up to date code examples than the blog > posts: > > http://www.bluishcoder.co.nz/factor-articles.pdf > > Chris. > -- > http://www.bluishcoder.co.nz > > > -- > The Next 800 Companies to Lead America's Growth: New Video Whitepaper > David G. Thomson, author of the best-selling book "Blueprint to a > Billion" shares his insights and actions to help propel your > business during the next growth cycle. Listen Now! > http://p.sf.net/sfu/SAP-dev2dev > ___ > Factor-talk mailing list > Factor-talk@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/factor-talk > > > -- > The Next 800 Companies to Lead America's Growth: New Video Whitepaper > David G. Thomson, author of the best-selling book "Blueprint to a > Billion" shares his insights and actions to help propel your > business during the next growth cycle. Listen Now! > http://p.sf.net/sfu/SAP-dev2dev > ___ > Factor-talk mailing list > Factor-talk@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/factor-talk > -- The Next 800 Companies to Lead America's Growth: New Video Whitepaper David G. Thomson, author of the best-selling book "Blueprint to a Billion" shares his insights and actions to help propel your business during the next growth cycle. Listen Now! http://p.sf.net/sfu/SAP-dev2dev ___ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk
Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations about Factor
Thanks Chris. I'm working on this now. I managed to get the Browser looking really good with the stylesheet tweak that kenanb suggested. Does anyone know how to change the font style and size in the Listener. Shaping -Original Message- From: Chris Double [mailto:chris.dou...@double.co.nz] Sent: 2010-November-09, 02:57 To: factor-talk@lists.sourceforge.net Subject: Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations about Factor On Tue, Nov 9, 2010 at 9:38 PM, Shaping wrote: > I need to be able to write a parser in a > straightforward way (XStreams-style maybe) using a PEG (collection of BNF > productions) so that I can experiment efficiently with this idea. Does > anyone have any experience with PEGs in Factor? Read the help for peg.ebnf. You can do this with the following in the listener: "peg.ebnf" about Also these blog posts: http://www.bluishcoder.co.nz/2007/11/embedded-grammars-in-factor.html http://www.bluishcoder.co.nz/2008/04/factor-parsing-dsl.html http://www.bluishcoder.co.nz/2008/06/parsing-javascript-with-factor.html The code in them is slightly out of date but combined with the peg.ebnf help you should be able to get the idea. There are a few peg.ebnf usage examples for a JavaScript grammar, a PL0 grammar and an expression calculator in the Factor source. My PDF of articles might have more up to date code examples than the blog posts: http://www.bluishcoder.co.nz/factor-articles.pdf Chris. -- http://www.bluishcoder.co.nz -- The Next 800 Companies to Lead America's Growth: New Video Whitepaper David G. Thomson, author of the best-selling book "Blueprint to a Billion" shares his insights and actions to help propel your business during the next growth cycle. Listen Now! http://p.sf.net/sfu/SAP-dev2dev ___ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk -- The Next 800 Companies to Lead America's Growth: New Video Whitepaper David G. Thomson, author of the best-selling book "Blueprint to a Billion" shares his insights and actions to help propel your business during the next growth cycle. Listen Now! http://p.sf.net/sfu/SAP-dev2dev ___ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk
Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations about Factor
On Tue, Nov 9, 2010 at 9:38 PM, Shaping wrote: > I need to be able to write a parser in a > straightforward way (XStreams-style maybe) using a PEG (collection of BNF > productions) so that I can experiment efficiently with this idea. Does > anyone have any experience with PEGs in Factor? Read the help for peg.ebnf. You can do this with the following in the listener: "peg.ebnf" about Also these blog posts: http://www.bluishcoder.co.nz/2007/11/embedded-grammars-in-factor.html http://www.bluishcoder.co.nz/2008/04/factor-parsing-dsl.html http://www.bluishcoder.co.nz/2008/06/parsing-javascript-with-factor.html The code in them is slightly out of date but combined with the peg.ebnf help you should be able to get the idea. There are a few peg.ebnf usage examples for a JavaScript grammar, a PL0 grammar and an expression calculator in the Factor source. My PDF of articles might have more up to date code examples than the blog posts: http://www.bluishcoder.co.nz/factor-articles.pdf Chris. -- http://www.bluishcoder.co.nz -- The Next 800 Companies to Lead America's Growth: New Video Whitepaper David G. Thomson, author of the best-selling book "Blueprint to a Billion" shares his insights and actions to help propel your business during the next growth cycle. Listen Now! http://p.sf.net/sfu/SAP-dev2dev ___ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk
Re: [Factor-talk] Furnace, XStreams (PEGs) and some observations about Factor
In context, I thought I was mentioning it after I had counseled you to try a factor code-compile-test cycle that wasn't perfectly what you desired to just get going and have fun. I just didn't want you to think I was trying to shut down non-orthodox ideas - factor to me represents just the opposite. Which I remember as a problem with forth - everyone did everything their own way and reinvented many wheels, so it was too hard to get started for a casual person. I sense that I'm running in too many directions with Factor. First, I need to get a minimal regular Emacs config that just works for me most of the time, like the one Slava is using in his video of Factor-with-Emacs, where he build the simple GUI app and the TCP time server. I'll do that tonight. I appreciated the tutorial showing very cogently how easy coding and co-testing are--in fact, how desirable testing-to-build is. This is one of Factor's best features. A testing "harness" doesn't get any lighter. I still have no significant stack discipline. I don't practice much code-writing yet. I'm still playing with demos, and reading about the language. I'm especially interested in Joe's OpenGL shader demo, Furnace and anything to do with composing and serving a blog (by this, I mean a very rich hypermedia document created by one person and viewed by many), and general-purpose PEG facilities, like those in VisualWorks XStreams framework: http://www.michaellucassmith.com/20100227%20Xtreams%20Primer.html http://www.michaellucassmith.com/20100428%20Xtreams%20marshaler.html http://www.michaellucassmith.com/20100502%20Xtream%20sharing.html) I am concerned that there is little to no drive among those here fluent in their Factor stack discipline/shuffle-patterns to build up and out of this layer or grade of words (one close to the metal) into a pure domain-level grammar (for any domain) free of shuffling or any need to be aware of it while using the domain-level words to do practical work, like configuring and starting a web server, for example. This separation of the layers seems difficult, and the bleed-through seems very common. Become good enough with your stack discipline, and soon you may not care much about simpler more approachable DSLs. That is my worry--that drive in this direction varies inversely with Factor stack discipline. I agree with prunedtree's recent comments, the gist of which is: if you are thinking about your domain logic and stack shuffling at the same time, you've messed up. I agree. Getting this layering effect in the vocabs to work without limiting machine-efficiency is my main goal. I want the optimizing compiler to be able to unswizzle the swizzles I create to ease human reading and thinking. I think some of this already happens, but do not know how far it goes. I'm noticing that Factor reading is not very efficient, because it taxes human memory. I know that I will be more fluent eventually, but, for now: I have the places on the stack to watch and to keep in order in my mind, the types of the entities in those slots to watch (in my mind because they are not often named), and the before/after stack state to remember or watch in the status bar, all in order to read Factor fluently, one word to the next. That process is heavy until stack discipline is firm and lots of memories of stack-effects have been cemented. I'm not sure that is a good basic constraint to have in a language. But I'm not convince that long self-documenting words (with extra bits about before/after stack state) are the answer, either. I'm hungry for local variables, now, though this goes against much of the basis of stack languages. I want lexical forms I can read and understand (parse with my mind, left-to-right, and down in a tree) to produce a known result (not a best guess). I don't want to remember a lot of stuff, because human memory is fragile and ultimately limits all programmers. I know that we have a "locals" vocab of some kind, but don't know how to use it. Is anyone using locals a lot in Factor just for readability? Can locals be used efficiently for the machine, too? How can locals be abused? I like explicitly clear code with a semantic focus on the values that are being produced, what they are named and where they live (stack, locals). Transitive verbs, so popular in all programming language, whether used in words or methods or functions or procedures or whatever are weak to useless at communicating what you are getting, where it's coming from and where it's landing. Verbs/action concepts in programming languages provide excellent background context for the values being computed during those verb/action intervals, but code that emphasizes them strongly without strong focus on values computed, tends to be noisy and hard to read/understand/remember/discuss. I want to work this focus on values into a basic CRUD DSL in Factor. I need to be able to write a parser in a straightforward wa
