Re: [basex-talk] Lookups and arrows
Thanks very much for this info, Christian! I'll pass your
observations on to the eXist team.
Joe
On Sun, Jan 10, 2016 at 3:50 AM, Christian Grün
<christian.gr...@gmail.com> wrote:
> Hi Tim, hi Joe,
>
> The query works if you use parentheses around the arrow operands:
>
> (json-doc("http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
> => json-doc())("@context")
>
> This is in compliance with the XQuery 3.1 spec [1].
>
> Out of interest, I spent some time and looked up the W3 bug tracker
> history, and I spotted a change in the precedence of the arrow
> operator [2]. Maybe this change is not reflected in eXist?
>
> Hope this helps,
> Christian
>
> [1] http://www.w3.org/TR/xquery-31/#doc-xquery31-ArrowExpr
> [2] https://www.w3.org/Bugs/Public/show_bug.cgi?id=27537
>
>
>
>
>> I tested your code with the closest thing at hand - a local build of
>> branch of Wolfgang Meier's eXist repo with support for the arrow
>> operator (https://github.com/wolfgangmm/exist/tree/feature/arrowop) -
>> and your code worked fine there. So my hunch is that there's a bug in
>> BaseX or some syntax error I'm not seeing in your code. For the
>> record, here's the code I'm running:
>>
>> --
>> xquery version "3.1";
>>
>> json-doc("http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
>> => json-doc()("@context")
>> --
>>
>> To check the results I actually use `=>
>> serialize(> xmlns="http://www.w3.org/2010/xslt-xquery-serialization;>jsonyes)`
>> on the results since eXist doesn't support adaptive serialization.
>>
>> I hope this is helpful.
>>
>> Joe
>>
>> On Sat, Jan 9, 2016 at 6:20 PM, Tim Thompson <timat...@gmail.com> wrote:
>>> Thanks, Joe! I guess I'd glossed over the "funky" example ;-) Regarding the
>>> arrow operator, I was wondering whether something like this was possible:
>>>
>>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context") =>
>>> json-doc()("@context")
>>>
>>> which throws an error: [XPST0003] Unexpected end of query: '("@context")'.
>>>
>>> Tim
>>>
>>> On Sat, Jan 9, 2016 at 3:53 PM, Joe Wicentowski <joe...@gmail.com> wrote:
>>>>
>>>> Hi Tim,
>>>>
>>>> For your first question, I think your example falls into what the spec
>>>> calls "funky looking" keys. See the 3rd bullet point example under
>>>> http://www.w3.org/TR/xquery-31/#id-lookup:
>>>>
>>>> > funky / >>> > @string"), an appropriate lookup for a map with rather odd conventions
>>>> > for
>>>> > keys.
>>>>
>>>> In other words, I think you're stuck with the ("@context") approach.
>>>>
>>>> As to your second question, it looks like what you're proposing should
>>>> work - but am I reading you as saying you get an error with your proposed
>>>> approach? If so, what's the error?
>>>>
>>>> Joe
>>>>
>>>> Sent from my iPad
>>>>
>>>> _
>>>> From: Tim Thompson <timat...@gmail.com>
>>>> Sent: Saturday, January 9, 2016 3:11 PM
>>>> Subject: [basex-talk] Lookups and arrows
>>>> To: BaseX <basex-talk@mailman.uni-konstanz.de>
>>>>
>>>>
>>>>
>>>> Hello,
>>>>
>>>> I'm testing some XQuery 3.1 features against a JSON-LD[1] document and had
>>>> a few questions. In the JSON-LD format, the "@" symbol has special
>>>> semantics
>>>> in key names, but seems to cause problems with the 3.1 lookup operator.
>>>>
>>>> For example:
>>>>
>>>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
>>>>
>>>> works as expected, but
>>>>
>>>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)?@context
>>>>
>>>> throws an error: [XPST0003] No specifier after lookup operator: '@'.
>>>>
>>>> Also, when using the "=>" operator, should it be possible to perform a
>>>> lookup on the last expression in a chain, if that expression returns a map?
>>>>
>>>> For example:
>>>>
>>>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
>>>> evaluates to " http://iiif.io/api/presentation/2/context.json;
>>>>
>>>> and
>>>>
>>>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context") =>
>>>> json-doc()
>>>>
>>>> returns another map object. So, how would one achieve this:
>>>>
>>>> json-doc(json-doc("
>>>> http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context"))("@context")
>>>>
>>>> using the arrow operator?
>>>>
>>>> Thanks,
>>>> Tim
>>>>
>>>>
>>>> [1] http://www.w3.org/TR/json-ld/
>>>>
>>>>
>>>> --
>>>> Tim A. Thompson
>>>> Metadata Librarian (Spanish/Portuguese Specialty)
>>>> Princeton University Library
>>>>
>>>>
>>>>
>>>
Re: [basex-talk] Lookups and arrows
Hi Tim, hi Joe,
The query works if you use parentheses around the arrow operands:
(json-doc("http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
=> json-doc())("@context")
This is in compliance with the XQuery 3.1 spec [1].
Out of interest, I spent some time and looked up the W3 bug tracker
history, and I spotted a change in the precedence of the arrow
operator [2]. Maybe this change is not reflected in eXist?
Hope this helps,
Christian
[1] http://www.w3.org/TR/xquery-31/#doc-xquery31-ArrowExpr
[2] https://www.w3.org/Bugs/Public/show_bug.cgi?id=27537
> I tested your code with the closest thing at hand - a local build of
> branch of Wolfgang Meier's eXist repo with support for the arrow
> operator (https://github.com/wolfgangmm/exist/tree/feature/arrowop) -
> and your code worked fine there. So my hunch is that there's a bug in
> BaseX or some syntax error I'm not seeing in your code. For the
> record, here's the code I'm running:
>
> --
> xquery version "3.1";
>
> json-doc("http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
> => json-doc()("@context")
> --
>
> To check the results I actually use `=>
> serialize( xmlns="http://www.w3.org/2010/xslt-xquery-serialization;>jsonyes)`
> on the results since eXist doesn't support adaptive serialization.
>
> I hope this is helpful.
>
> Joe
>
> On Sat, Jan 9, 2016 at 6:20 PM, Tim Thompson <timat...@gmail.com> wrote:
>> Thanks, Joe! I guess I'd glossed over the "funky" example ;-) Regarding the
>> arrow operator, I was wondering whether something like this was possible:
>>
>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context") =>
>> json-doc()("@context")
>>
>> which throws an error: [XPST0003] Unexpected end of query: '("@context")'.
>>
>> Tim
>>
>> On Sat, Jan 9, 2016 at 3:53 PM, Joe Wicentowski <joe...@gmail.com> wrote:
>>>
>>> Hi Tim,
>>>
>>> For your first question, I think your example falls into what the spec
>>> calls "funky looking" keys. See the 3rd bullet point example under
>>> http://www.w3.org/TR/xquery-31/#id-lookup:
>>>
>>> > funky / >> > @string"), an appropriate lookup for a map with rather odd conventions for
>>> > keys.
>>>
>>> In other words, I think you're stuck with the ("@context") approach.
>>>
>>> As to your second question, it looks like what you're proposing should
>>> work - but am I reading you as saying you get an error with your proposed
>>> approach? If so, what's the error?
>>>
>>> Joe
>>>
>>> Sent from my iPad
>>>
>>> _
>>> From: Tim Thompson <timat...@gmail.com>
>>> Sent: Saturday, January 9, 2016 3:11 PM
>>> Subject: [basex-talk] Lookups and arrows
>>> To: BaseX <basex-talk@mailman.uni-konstanz.de>
>>>
>>>
>>>
>>> Hello,
>>>
>>> I'm testing some XQuery 3.1 features against a JSON-LD[1] document and had
>>> a few questions. In the JSON-LD format, the "@" symbol has special semantics
>>> in key names, but seems to cause problems with the 3.1 lookup operator.
>>>
>>> For example:
>>>
>>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
>>>
>>> works as expected, but
>>>
>>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)?@context
>>>
>>> throws an error: [XPST0003] No specifier after lookup operator: '@'.
>>>
>>> Also, when using the "=>" operator, should it be possible to perform a
>>> lookup on the last expression in a chain, if that expression returns a map?
>>>
>>> For example:
>>>
>>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
>>> evaluates to " http://iiif.io/api/presentation/2/context.json;
>>>
>>> and
>>>
>>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context") =>
>>> json-doc()
>>>
>>> returns another map object. So, how would one achieve this:
>>>
>>> json-doc(json-doc("
>>> http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context"))("@context")
>>>
>>> using the arrow operator?
>>>
>>> Thanks,
>>> Tim
>>>
>>>
>>> [1] http://www.w3.org/TR/json-ld/
>>>
>>>
>>> --
>>> Tim A. Thompson
>>> Metadata Librarian (Spanish/Portuguese Specialty)
>>> Princeton University Library
>>>
>>>
>>>
>>
Re: [basex-talk] Lookups and arrows
Hi Tim,
For your first question, I think your example falls into what the spec calls
"funky looking" keys. See the 3rd bullet point example under
http://www.w3.org/TR/xquery-31/#id-lookup:
> funky / an appropriate lookup for a map with rather odd conventions for keys.
In other words, I think you're stuck with the ("@context") approach.
As to your second question, it looks like what you're proposing should work -
but am I reading you as saying you get an error with your proposed approach?
If so, what's the error?
Joe
Sent from my iPad
_
From: Tim Thompson <timat...@gmail.com>
Sent: Saturday, January 9, 2016 3:11 PM
Subject: [basex-talk] Lookups and arrows
To: BaseX <basex-talk@mailman.uni-konstanz.de>
Hello,
I'm testing some XQuery 3.1 features against a JSON-LD[1] document
and had a few questions. In the JSON-LD format, the "@" symbol has special
semantics in key names, but seems to cause problems with the 3.1 lookup
operator.
For example:
json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
works as expected, but
json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)?@context
throws an error: [XPST0003] No specifier after lookup operator: '@'.
Also, when using the "=>" operator, should it be possible to perform a
lookup on the last expression in a chain, if that expression returns a map?
For example:
json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
evaluates to " http://iiif.io/api/presentation/2/context.json;
and
json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context") =>
json-doc()
returns another map object. So, how would one achieve this:
json-doc(json-doc("
http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context"))("@context")
using the arrow operator?
Thanks,
Tim
[1]http://www.w3.org/TR/json-ld/
--
Tim A. Thompson
Metadata Librarian (Spanish/Portuguese Specialty)
Princeton University Library
[basex-talk] Lookups and arrows
Hello,
I'm testing some XQuery 3.1 features against a JSON-LD[1] document and had
a few questions. In the JSON-LD format, the "@" symbol has special
semantics in key names, but seems to cause problems with the 3.1 lookup
operator.
For example:
json-doc("http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
works as expected, but
json-doc("http://lae.princeton.edu/catalog/0bp35.jsonld;)?@context
throws an error: [XPST0003] No specifier after lookup operator: '@'.
Also, when using the "=>" operator, should it be possible to perform a
lookup on the last expression in a chain, if that expression returns a map?
For example:
json-doc("http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
evaluates to "http://iiif.io/api/presentation/2/context.json;
and
json-doc("http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context") =>
json-doc()
returns another map object. So, how would one achieve this:
json-doc(json-doc("http://lae.princeton.edu/catalog/0bp35.jsonld
")("@context"))("@context")
using the arrow operator?
Thanks,
Tim
[1] http://www.w3.org/TR/json-ld/
--
Tim A. Thompson
Metadata Librarian (Spanish/Portuguese Specialty)
Princeton University Library
Re: [basex-talk] Lookups and arrows
Thanks, Joe! I guess I'd glossed over the "funky" example ;-) Regarding the
arrow operator, I was wondering whether something like this was possible:
json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context") =>
json-doc()("@context")
which throws an error: [XPST0003] Unexpected end of query: '("@context")'.
Tim
On Sat, Jan 9, 2016 at 3:53 PM, Joe Wicentowski <joe...@gmail.com> wrote:
> Hi Tim,
>
> For your first question, I think your example falls into what the spec
> calls "funky looking" keys. See the 3rd bullet point example under
> http://www.w3.org/TR/xquery-31/#id-lookup:
>
> > funky / @string"), an appropriate lookup for a map with rather odd conventions for
> keys.
>
> In other words, I think you're stuck with the ("@context") approach.
>
> As to your second question, it looks like what you're proposing should
> work - but am I reading you as saying you get an error with your proposed
> approach? If so, what's the error?
>
> Joe
>
> Sent from my iPad
>
> _____________
> From: Tim Thompson <timat...@gmail.com>
> Sent: Saturday, January 9, 2016 3:11 PM
> Subject: [basex-talk] Lookups and arrows
> To: BaseX <basex-talk@mailman.uni-konstanz.de>
>
>
>
> Hello,
>
> I'm testing some XQuery 3.1 features against a JSON-LD[1] document and had
> a few questions. In the JSON-LD format, the "@" symbol has special
> semantics in key names, but seems to cause problems with the 3.1 lookup
> operator.
>
> For example:
>
> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
>
> works as expected, but
>
> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)?@context
>
> throws an error: [XPST0003] No specifier after lookup operator: '@'.
>
> Also, when using the "=>" operator, should it be possible to perform a
> lookup on the last expression in a chain, if that expression returns a map?
>
> For example:
>
> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
> evaluates to " http://iiif.io/api/presentation/2/context.json;
>
> and
>
> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context") =>
> json-doc()
>
> returns another map object. So, how would one achieve this:
>
> json-doc(json-doc("
> http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context"))("@context")
>
>
> using the arrow operator?
>
> Thanks,
> Tim
>
>
> [1] http://www.w3.org/TR/json-ld/
>
>
> --
> Tim A. Thompson
> Metadata Librarian (Spanish/Portuguese Specialty)
> Princeton University Library
>
>
>
>
Re: [basex-talk] Lookups and arrows
Hi Tim,
"Funky" made me chuckle too!
I tested your code with the closest thing at hand - a local build of
branch of Wolfgang Meier's eXist repo with support for the arrow
operator (https://github.com/wolfgangmm/exist/tree/feature/arrowop) -
and your code worked fine there. So my hunch is that there's a bug in
BaseX or some syntax error I'm not seeing in your code. For the
record, here's the code I'm running:
--
xquery version "3.1";
json-doc("http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
=> json-doc()("@context")
--
To check the results I actually use `=>
serialize(http://www.w3.org/2010/xslt-xquery-serialization;>jsonyes)`
on the results since eXist doesn't support adaptive serialization.
I hope this is helpful.
Joe
On Sat, Jan 9, 2016 at 6:20 PM, Tim Thompson <timat...@gmail.com> wrote:
> Thanks, Joe! I guess I'd glossed over the "funky" example ;-) Regarding the
> arrow operator, I was wondering whether something like this was possible:
>
> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context") =>
> json-doc()("@context")
>
> which throws an error: [XPST0003] Unexpected end of query: '("@context")'.
>
> Tim
>
> On Sat, Jan 9, 2016 at 3:53 PM, Joe Wicentowski <joe...@gmail.com> wrote:
>>
>> Hi Tim,
>>
>> For your first question, I think your example falls into what the spec
>> calls "funky looking" keys. See the 3rd bullet point example under
>> http://www.w3.org/TR/xquery-31/#id-lookup:
>>
>> > funky / > > @string"), an appropriate lookup for a map with rather odd conventions for
>> > keys.
>>
>> In other words, I think you're stuck with the ("@context") approach.
>>
>> As to your second question, it looks like what you're proposing should
>> work - but am I reading you as saying you get an error with your proposed
>> approach? If so, what's the error?
>>
>> Joe
>>
>> Sent from my iPad
>>
>> _
>> From: Tim Thompson <timat...@gmail.com>
>> Sent: Saturday, January 9, 2016 3:11 PM
>> Subject: [basex-talk] Lookups and arrows
>> To: BaseX <basex-talk@mailman.uni-konstanz.de>
>>
>>
>>
>> Hello,
>>
>> I'm testing some XQuery 3.1 features against a JSON-LD[1] document and had
>> a few questions. In the JSON-LD format, the "@" symbol has special semantics
>> in key names, but seems to cause problems with the 3.1 lookup operator.
>>
>> For example:
>>
>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
>>
>> works as expected, but
>>
>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)?@context
>>
>> throws an error: [XPST0003] No specifier after lookup operator: '@'.
>>
>> Also, when using the "=>" operator, should it be possible to perform a
>> lookup on the last expression in a chain, if that expression returns a map?
>>
>> For example:
>>
>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context")
>> evaluates to " http://iiif.io/api/presentation/2/context.json;
>>
>> and
>>
>> json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context") =>
>> json-doc()
>>
>> returns another map object. So, how would one achieve this:
>>
>> json-doc(json-doc("
>> http://lae.princeton.edu/catalog/0bp35.jsonld;)("@context"))("@context")
>>
>> using the arrow operator?
>>
>> Thanks,
>> Tim
>>
>>
>> [1] http://www.w3.org/TR/json-ld/
>>
>>
>> --
>> Tim A. Thompson
>> Metadata Librarian (Spanish/Portuguese Specialty)
>> Princeton University Library
>>
>>
>>
>
