Re: [MacPerl] find value in array

[Bart Lateur <bart.lateur@skynet.be>]

On Wed, 18 Oct 2000 08:38:15 -0700, John W Baxter wrote:

>>> Cool. The expression $list['0 but true'] works like $list[0] !!
>>
>>Perl even goes so far as to special case the string '0 but true'; when it
>>is converted to a number, Perl does not produce an "argument is not
>>numeric" warning.
>
>That's not a special case...try
>
>print 0 + "77 seventy-seven" + "\n";
>
>When a number is needed and Perl has a string, it converts as much of the
>string as possible to a number and uses that.

Oh, blimey: far too many people seem to be running Perl code without
warnings enabled. It does catch a lot of bugs, you know!

	$^W = 1;
	print 0 + "77 and the rest";
-->
     Argument "77 and the rest" isn't numeric in addition (+) at test.pl
     line 3.
     77	

>Hence, "twenty" == "thirty" is true, since both are 0.

That's true. That's one of the typical bugs that -w will catch.

The special thing is that there is NO warning for the conversion of the
string "0 but true" to a number. The value will be zero, obviously.

OTOH, it's not the only string for which this is the case: other zero
valued strings are True as well: "0E0", "0.000", ".0", "0.", "-0". All
zero, all true. So this exception was actualy unnecessary.

-- 
	Bart.

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