in reply to Easy Reference for Contexts

There ought to be a repository of common expressions and how they behave in each context
The perl documentation does that, doesn't it? perlop and perlfunc would be the places to look first.
what their default context is
There's no default context. An expression is always in a context. And it's always the caller that determines the context - there's no operator/function that says "you know what, I let my operands run in their default context". (And how could it?)

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Re^2: Easy Reference for Contexts (POD-Extension)
by LanX (Saint) on Apr 14, 2011 at 12:37 UTC
    > > what their default context is
    > There's no default context.

    with a little more tolerance in interpretation of "context":

    IIRC some operands and builtins only work in special contexts, some even throw (threw?) warnings if not used properly.

    > > There ought to be a repository of common expressions and how they behave in each context
    > The perl documentation does that, doesn't it?

    Well I once meditated over this, unfortunately POD doesn't have a standard notation for a brief definition for the interface of a term.

    If it had, they could not only automatically be compiled into cheat sheets, but also into tool tips for IDEs or grammatical rules for syntax checkers.

    There are various alternative sources for such abstracts, which get hopelessly fast outdated

    For instance emacs's cperl-mode has tool-tips hardcoded which are far from being up-to-date.

    <Reveal this spoiler or all in this thread>

    Another advantage of such an hypothetical POD-extension could be the definition of use cases for snippet-expansion within an IDE, like for yasnippet in emacs or more detailed error-texts for diagnostics.

    Of course some (all?) of this could be achieved with a special =FOR :format-paragraph, but there is no standard notation yet. (maybe Perl6 signatures could be a good start)

    Cheers Rolf

[reply]
[d/l]
[select]
      Padre/../PPI? B::Deparse::ContextAnnotate? Perl::Tidy::ContextAnnotate?

      Hmm ... delicious ideas .... ...

      … … … .__,,,_._,--~~~~~---,,_
      … … ,,-"… .,~". . . . . . . . . . . . ."~-,
      … …,/-~-,-". . . . . . . . . . . . . . . . . . ."~,,___
      … ,-".|..,-". . . . . . . . . . . . . . . . . . . . . . . . .~'~--,,_
      ... /… \". . . . . . . . . . . . . . . . . . . . . . . . . . . . . __,'\
      … \..,/."-. . . . . . . . . . . . . . . . . . . . . ."~,,. .,,-~'--': : |
      … ."-'. . . . . . . . . . . . . . . . . . . . . . ._,,-~'\": : :,~"``"~,
      … ..|.". . . . . . . . . . . . . . . . . . . ,-,": : : : : :|:,,-". . . . . |
      … ..|. . . . . . . . . . . . . . \. . . . ,-"~': : : : : : /. . . . . . . ./~---,,_
      … ...\. . . . . . . . . . . . . . \. . ,-": : : : : : : : /. . . . . ,-~"'………."~-,
      … … '\. . . . . . . . . . . . . .",": : : : : : : _,-". . . ,-~"…………………"\
      … … .."-,. . . ,_. . . . . . . . Ż"~~----~". . . ,-~"…………….._,,--~,,../
      … … … ."~,. . \,"~,_. . . . . . . . . . . . . .,-"……………,,~": :,,,-,'~',/
      … … … … ,",-,. "-,. ."~. . . . . . . . . . ,-"………….,~":,,,,,--":,-".,-"
      … … … … ."-,.."~,". _,. . . . . . . . . ,/…………,~": ,-",-"_,"".,-"
      … … … … … \… ,-". __, . . . . . . ,/………...,-": ,"';/Ż,"…,~"
      … … … … … … .\. .".\. . .,. . . . ./……….,-"_,,-";;;\,/..,-"
      … … … … … … ..."~~-,--". . . ./………,-": /;;;;;;;;;/../
      … … … … … … … … .|. . . . . |……..,/~~';;;;;;;;;;;|...'\,
      … … … … … … … … .|. . . . . |……./;,-~~--,-~~-,"-….|
      … … … … … … … … .|. . . . . .\…...|-"::::::::":::::::\... |
      … … … … … … … .SL|. . . . . . \,….."--,--"-,:::::::::/..,/
      … … … … … … … … .|. . . . . . . "~,……ŻŻ"~--~"..,/
      … … … … … … … … .|. . . . . . . . . ."~~---,,,,,,--~"\
      … … … … … … … … ..ŻŻ"'~~~~---------,,,,,,,,,_____\
      ---
[reply]
        How comes you're better in drawing ascii-pictures than linking to CPAN? :)

        Cheers Rolf

        UPDATE: ehm still confused about your cryptic message...PPI, B::Deparse, Perl::Tidy are not POD-parser...

[reply]

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