Re^2: My problems to understand the Perl documentation

in reply to Re: My problems to understand the Perl documentation [updated]
in thread My problems to understand the Perl documentation

Thank you jo37 for your work!

This is not true, it gives (99).

Sorry, I had an error in my test script. Now I also get 99.

Your example made me understand that a prototype also defines the context (scalar/list) for the evaluation of the arguments.

My point is that the function split is not fully described in the Perl documentation

Reading index-functions I get the impression that split is a function.
In perlsub is stated:

The Perl model for function call and return values is simple: all functions are passed as parameters one single flat list of scalars, and all functions likewise return to their caller one single flat list of scalars. ...

The function prototype returns the prototype of a function as a string (or undef if the function has no prototype).
prototype "CORE::split" returns undef (Thanks LanX )

My conclusion from this is that split is a Perl sub, without prototype.

I have however realized that:

Split's first argument, /PATTERN/, is not evaluated immediately. In some way it is kept for later usage.
The rest of the arguments are not treated like a Perl sub without prototype.

Somewhere in split this differences from a normal Perl sub should be included. As split behaves more like an operator it is perhaps better to call it an operator. It is also implemented as an operator and not as a Perl sub.

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Re^3: My problems to understand the Perl documentation by haukex (Archbishop) on Aug 24, 2020 at 08:44 UTC
Reading index-functions I get the impression that split is a function. That list also includes things that are clearly not a function, like `and`, `__END__`, and `m`. The function prototype returns the prototype of a function as a string (or undef if the function has no prototype). prototype "CORE::split" returns undef You seem to be ignoring the part of that doc that says: If FUNCTION is a string starting with `CORE::`, the rest is taken as a name for a Perl builtin. If the builtin's arguments cannot be adequately expressed by a prototype (such as system), prototype returns undef, because the builtin does not really behave like a Perl function. As split behaves more like an operator it is perhaps better to call it an operator. Please read carefully Terms and List Operators (Leftward): Actually, there aren't really functions in this sense, just list operators and unary operators behaving as functions because you put parentheses around the arguments. Several things in Perl only make sense when you read all of the documentation.	[reply] [d/l] [select]
Re^3: My problems to understand the Perl documentation by LanX (Saint) on Aug 24, 2020 at 18:58 UTC
Split IS a builtin function. I told you already that the fact you can't easily replicate it with `sub` doesn't mean it's not a function. Perl is not Lisp where the whole syntax can be expressed with one single s-expression . Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply]
Re^3: My problems to understand the Perl documentation by LanX (Saint) on Aug 24, 2020 at 19:11 UTC
> Reading index-functions I get the impression that split is a function. That's taken from `perlfunc` and there it clearly states Here are Perl's functions (including things that look like functions, like some keywords and named operators* ) arranged by category.* It should better have been named "keyword-index" Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply]
Re^3: My problems to understand the Perl documentation by jo37 (Deacon) on Aug 23, 2020 at 19:42 UTC
My conclusion from this is that split is a Perl sub, without prototype. Is there any built-in without a prototype? I don't think so. Greetings, -jo `$gryYup$d0ylprbpriprrYpkJl2xyl~rzg??P~5lp2hyl0p$`	[reply]
Re^4: My problems to understand the Perl documentation by LanX (Saint) on Aug 23, 2020 at 21:52 UTC
> Is there any built-in without a prototype? I don't think so. Yes, several. You can check yourself with `prototype` From the docs: If FUNCTION is a string starting with CORE:: , the rest is taken as a name for a Perl builtin. If the builtin's arguments cannot be adequately expressed by a prototype (such as system), prototype returns undef, because the builtin does not* really behave like a Perl function.* Otherwise, the string describing the equivalent prototype is returned. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply]
Re^4: My problems to understand the Perl documentation by haukex (Archbishop) on Aug 24, 2020 at 07:31 UTC
Is there any built-in without a prototype? On 5.28, prototype returns `undef` for at least the following (I may have missed a few, and I omitted most things that I think most people would classify as keywords and operators instead of functions, like `use`, `goto`, and -X): `chomp chop defined delete do eval exec exists grep map print printf require return say select sort split system` [download] Added minor clarifications.	[reply] [d/l] [select]
Re^5: My problems to understand the Perl documentation by LanX (Saint) on Aug 24, 2020 at 16:06 UTC
> most people would classify as keywords and operators instead of functions For me any reserved word is a keyword, this includes functions. I know what you mean but "keyword" doesn't describe it. See also perlfunc#Perl-Functions-by-Category ... which is even more confusing. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply]
Re^6: My problems to understand the Perl documentation by haukex (Archbishop) on Aug 24, 2020 at 19:08 UTC
Re^7: My problems to understand the Perl documentation (Terminology) by LanX (Saint) on Aug 24, 2020 at 19:46 UTC
Re^7: My problems to understand the Perl documentation by LanX (Saint) on Aug 26, 2020 at 21:33 UTC

In Section Meditations