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%22)(%22@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 joewiz@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 / <looking @string") is equivalent to .("$funky / <looking
@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 timathom@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%22)(%22@context")
works as expected, but
json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld%22)?@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%22)(%22@context") evaluates to " http://iiif.io/api/presentation/2/context.json"
and
json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld%22)(%22@context") => json-doc()
returns another map object. So, how would one achieve this:
json-doc(json-doc(" http://lae.princeton.edu/catalog/0bp35.jsonld%22)(%22@context%22))(%22@conte...")
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