At which line number did the print statement occure?

jeanluca has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: At which line number did the print statement occur? by davorg (Chancellor) on Oct 13, 2006 at 13:19 UTC
`print 'This is line ', __LINE__;` [download] -- <http://dave.org.uk> "The first rule of Perl club is you do not talk about Perl club." -- Chip Salzenberg	[reply] [d/l]
Re^2: At which line number did the print statement occure? by monarch (Priest) on Oct 13, 2006 at 13:26 UTC
Another good one to remember is `__FILE__`.	[reply] [d/l]
Re^3: At which line number did the print statement occure? by jeanluca (Deacon) on Oct 13, 2006 at 13:41 UTC
or $0 Do you know where are all the __LINE__, __FILE__ or __PACKAGE__ documented ? Thnx!	[reply]
Re^4: At which line number did the print statement occure? by davorg (Chancellor) on Oct 13, 2006 at 13:48 UTC
Re^5: At which line number did the print statement occure? by Sartak (Hermit) on Oct 13, 2006 at 17:32 UTC
Some notes below your chosen depth have not been shown here
Re^4: At which line number did the print statement occure? by Anonymous Monk on Oct 13, 2006 at 13:49 UTC
Re: At which line number did the print statement occure? by bart (Canon) on Oct 13, 2006 at 14:01 UTC
If you don't really want to use warn, which adds the line number by default, then you can replace the print with your own sub, in which you can use caller to check where the sub got called from: `($package, $filename, $line) = caller;` [download] That should suffice to recreate what warn does. You can get lots more of info back, if you use a parameter to caller: `($package, $filename, $line, @blahblah) = caller(0);` [download] For example: `#! perl -w report("Hello, world!"); sub report { my ($package, $filename, $line) = caller; print "print from $filename line $line: @_\n"; }` [download] Output: print from test.pl line 3: Hello, world!	[reply] [d/l] [select]
Re: At which line number did the print statement occure? by jbert (Priest) on Oct 13, 2006 at 13:45 UTC
and it's worth remembering that if you don't put a newline on the end of a warn() (or die()) you'll get the file and line number of the script printed.	[reply]
Re: At which line number did the print statement occure? by mrpeabody (Friar) on Oct 14, 2006 at 05:29 UTC
__LINE__ and friends should be documented in perlvar as well as perldata. perlvar is the logical place to look for this functionality.	[reply]
Re^2: At which line number did the print statement occure? by jrockway (Acolyte) on Oct 16, 2006 at 02:42 UTC
They're data, not variables. (Vary as in change.) Plus, they look a lot like __DATA__ and __END__, which are documented in perldata.	[reply]
Re^3: At which line number did the print statement occure? by Bro. Doug (Monk) on Oct 17, 2006 at 23:51 UTC
It's worth noting that the function caller, when used in Windows, returns the line from the first line of actual code. `#! /usr/bin/perl -w foo() ; sub foo{ print join(" ", caller); }` [download] This will print '3' as the line number on my Windows machine. Bro. Doug :wq	[reply] [d/l]