No output from log:callWithOptional or log:bound

[tpluscode]

Based on a discussion, we created a rule similar to that below.

It works in eye but there is not output when switched to eye-js.

@prefix log: <http://www.w3.org/2000/10/swap/log#>.
@prefix : <http://example.com/>.

:object1 :Title :title1.
:title1 :Type :type1.
:object2 :Title :title2.
:object3 :Title :title3.
:title3 :Type :type3.

{
  {
    ?object :Title ?title.
  } log:callWithOptional {
    ?title :Type ?type.
  }.
  ?type log:bound false.
} => {
  ?object :TitleWithoutType ?title.
}.

https://n3-editor.herokuapp.com/n3/editor/s/QjFkNFED

[josd]

@william-vw would it be possible to work with the latest eye-js that is https://eyereasoner.github.io/eye-js/latest/index.js instead of https://eyereasoner.github.io/eye-js/3/latest/index.js ?
Or if not possible, then at least work with https://eyereasoner.github.io/eye-js/4/latest/index.js

[tpluscode]

Oh, the UI is using an old version? That's a red herring apparently

We are still having issues with the JS lib, but as it turns out, only when passing in quads:
https://runkit.com/embed/xa0qvolbwp7s

When the input is an n3 string, the output is as expected: https://runkit.com/embed/aywnzamumxq0

Problem with n3 parser?

[tpluscode]

AHA, got it. Here's what happens. When we pass in parsed quads, they get serialised by the JS in a different order

{
  ?type <http://www.w3.org/2000/10/swap/log#bound> false .
  {
    ?object <http://example.com/Title> ?title .
  }
  <http://www.w3.org/2000/10/swap/log#callWithOptional> {
    ?title <http://example.com/Type> ?type .
  } .
} => {
  ?object <http://example.com/TitleWithoutType> ?title .
} .

<http://example.com/object1> <http://example.com/Title> <http://example.com/title1> .
<http://example.com/title1> <http://example.com/Type> <http://example.com/type1> .
<http://example.com/object2> <http://example.com/Title> <http://example.com/title2> .
<http://example.com/object3> <http://example.com/Title> <http://example.com/title3> .
<http://example.com/title3> <http://example.com/Type> <http://example.com/type3> .

Written this way, the output of eye is also wrong: https://n3-editor.herokuapp.com/n3/editor/s/LEtH5WsO

[josd]

You are right, this is indeed order dependent and we added a log:call to impose an order: first call subject, then call object.
So with

{
    {
        {
            ?object <http://example.com/Title> ?title .
        } <http://www.w3.org/2000/10/swap/log#callWithOptional> {
            ?title <http://example.com/Type> ?type .
        } .
    } <http://www.w3.org/2000/10/swap/log#call> {
        ?type <http://www.w3.org/2000/10/swap/log#bound> false .
    } .
} => {
  ?object <http://example.com/TitleWithoutType> ?title .
} .

<http://example.com/object1> <http://example.com/Title> <http://example.com/title1> .
<http://example.com/title1> <http://example.com/Type> <http://example.com/type1> .
<http://example.com/object2> <http://example.com/Title> <http://example.com/title2> .
<http://example.com/object3> <http://example.com/Title> <http://example.com/title3> .
<http://example.com/title3> <http://example.com/Type> <http://example.com/type3> .

and EYE v3.10.0 it should just give

<http://example.com/object2> <http://example.com/TitleWithoutType> <http://example.com/title2>.

[tpluscode]

So log:call is something new added only in 3.10?

[josd]

Yes indeed it is added in EYE v3.10.0 and PH2 v1.1.0

[william-vw]

@william-vw would it be possible to work with the latest eye-js that is https://eyereasoner.github.io/eye-js/latest/index.js instead of https://eyereasoner.github.io/eye-js/3/latest/index.js ? Or if not possible, then at least work with https://eyereasoner.github.io/eye-js/4/latest/index.js

Ok - I switched the editor to https://eyereasoner.github.io/eye-js/latest/index.js

[josd]

Great and thanks a lot @william-vw !
https://n3-editor.herokuapp.com/n3/editor/s/z8ZKamOl now works perfectly with eye-js

[tpluscode]

You are right, this is indeed order dependent and we added a log:call to impose an order: first call subject, then call object.

I am slightly surprised by this. When parsed, triples have not order. I see how the graphs are chained together by log:call but should that be even necessary?

Given rule like the original above, wouldn't it be possible to determine that the value of ?title needs to be evaluated before the :TitleWithoutType pattern? Regardless of the order of triples...

[josd]

IMHO there is no general algorithm to do a reordering for any kind of premise triples.

[jeswr]

Written this way, the output of eye is also wrong: https://n3-editor.herokuapp.com/n3/editor/s/LEtH5WsO

@josd - should this issue be transferred to https://github.com/eyereasoner/eye?

[josd]

The log:bound built-in is order dependent and the order can be imposed with log:call like done in #82 (comment)
For this particular case we could shift log:bound to the last position of the premis, but IMHO there is no general rule to fix order dependent issues. See also #25