Re: Re2: line number

dmitri said:

   $linenum = &{sub{(caller)[2]}};
[download]

blakem said:

   $linenum = __LINE__;
[download]

dmitri's solution returns the line number of ~~the call to~~the line in the current subroutine.

blakem's solution returns the line number of the __LINE__ within the current subroutine.

Amended 4:10p PDT I'm not sure why dmitri is building a subroutine reference only to call it. dmitri, do you care to clarify?

At 4:15, after reading blakem's follow-up, I realize blakem is right. dmitri's would be different, if he'd said:

  $linenum = (caller)[2];
[download]

but he didn't. So they are equivalent, and I must say that __LINE__ is much simpler.

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Re:4: line number by blakem (Monsignor) on Sep 12, 2002 at 23:09 UTC
dmitri's solution returns the line number of the call to the current subroutine. Yes, but the two are the same. The "current subroutine" (as far as `caller()` is concerned) is the one created right there on that line. `$linenum = &{sub{(caller)[2]}};` [download] Its creating and calling a sub whose sole purpose is to find the linenumber of its caller. Its like phoning a friend to ask what number shows up on his caller ID... Why bother when your own phone number is pasted right there on the front of your phone? -Blake	[reply] [d/l] [select]
Re: Re: Re2: line number by dmitri (Priest) on Sep 13, 2002 at 16:17 UTC
I dont have the code where I used this thing. I remember that for some reason I could not use __LINE__; it could have been within an eval.	[reply]
Re4: line number by blakem (Monsignor) on Sep 14, 2002 at 11:14 UTC
OK, thats what I was interested in. Both `__LINE__` and `caller()` border on the black magic side of perl (grey magic anyone???) I was wondering if you had found a place where the two didn't agree. -Blake	[reply] [d/l] [select]


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