Re: Re: Answer: How do I find the index of the last element in an array?

in reply to Re: Answer: How do I find the index of the last element in an array?
in thread How do I find the index of the last element in an array?

If foo is an empty, or undefined, array, then @foo is undef, but $#foo is -1.

In such a case, $#foo does equal scalar(@foo)-1, but scalar(@foo) does not equal $#foo+1.

--
Tommy
Too stupid to live.
Too stubborn to die.

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Re: Re: Re: Answer: How do I find the index of the last element in an array? by edan (Curate) on Jun 02, 2003 at 14:41 UTC
No, I don't think so. If `@foo` is empty, then `scalar(@foo)` is zero, not undef, and the equality holds true... (actually `undef == 0` is also true, though it emits a warning) The only time `@foo != $#foo + 1` is when you messed with `$[` (but you didn't do that, did you?) -- 3dan	[reply] [d/l] [select]
Re: Re: Re: Re: Answer: How do I find the index of the last element in an array? by tommyw (Hermit) on Jun 02, 2003 at 14:50 UTC
Ack. Damn those non-scalar contexts! `perl -e 'print $#a, "\n", @a, "\n", $#a+1, "\n"' -1 0` [download] Thus clearly showing that @a is undef. Which is true. In a list context... If I'd remembered to include scalar around it: `perl -e 'print $#a, "\n", scalar (@a), "\n", $#a+1, "\n"' -1 0 0` [download] , I'd have got the right answer... My bad. -- Tommy Too stupid to live. Too stubborn to die.	[reply] [d/l] [select]

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