•Re^5: How to de-reference a coderef?

in reply to Re^4: How to de-reference a coderef?
in thread How to de-reference a coderef?

To make that even simpler, you could write a subroutine called Sub that takes a coderef argument and records its file and line number and returns an object that when used as a coderef invokes the coderef, but when used as a string returns the filename/linenumber of creation. How's that for slick? I may even have to code that up for a snippet. Usage would be something like:

my $sub = Sub { my $x = shift; print $x };
$sub->("foo"); # prints foo
print "that was from $sub\n";
[download]

Pretty simple to do.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

update: see Track the filename/line number of an anonymous coderef.

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Re^6: How to de-reference a coderef? by Anonymous Monk on Dec 09, 2004 at 20:50 UTC
I'd like to see this, namely as in my head I can only imagine the syntax of... my $sub = Sub sub { my $x = shift; print $x }; Being that I thought { } was the anonymous hash composer. I'm really curious about this though, and syntax reduction in general. Writing things that act like Ruby/Groovy blocks is kind of ugly when you have to use the sub keyword all of the time.	[reply]
•Re^7: How to de-reference a coderef? by merlyn (Sage) on Dec 10, 2004 at 00:06 UTC
Well, a trivial implementation of `Sub` is `sub Sub (&) { return shift }` [download] but that doesn't do the blessing and overloading. You'll get to use the syntax of: `my $s = Sub { print +shift } $s->('hello');` [download] just as I indicated before. -- Randal L. Schwartz, Perl hacker Be sure to read my standard disclaimer if this is a reply.	[reply] [d/l] [select]

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