Re: Lexical variables question

$var will be defined, but false. Try if ($var) instead.

------
We are the carpenters and bricklayers of the Information Age.

The idea is a little like C++ templates, except not quite so brain-meltingly complicated. -- TheDamian, Exegesis 6

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.

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Re: Re: Lexical variables question by edan (Curate) on Aug 12, 2003 at 15:24 UTC
In addition to davorg's valid criticism, your `if ($var)` test is less-than-optimal if zero is a valid value for the param, which it probably is... -- 3dan	[reply]
Re: Re: Lexical variables question by davorg (Chancellor) on Aug 12, 2003 at 14:34 UTC
`$var` will be defined, but false. Try `if ($var)` instead. Why do you think that `$var` can't be "undef"? If `param` returns "undef" then `$var` will be undefined. -- <http://www.dave.org.uk> "The first rule of Perl club is you do not talk about Perl club." -- Chip Salzenberg	[reply]
Re3: Lexical variables question by dragonchild (Archbishop) on Aug 12, 2003 at 15:25 UTC
Because it won't be undef from a checkbox. That was the real question from the OP. It will be undef if the name is wrong. It will be defined if the name is there and is a checkbox. It will be ''. ------ We are the carpenters and bricklayers of the Information Age. The idea is a little like C++ templates, except not quite so brain-meltingly complicated. -- TheDamian, Exegesis 6 Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.	[reply]
Re: Re3: Lexical variables question by davorg (Chancellor) on Aug 12, 2003 at 15:35 UTC
Because it won't be undef from a checkbox. Who said anything about a checkbox? In fact, who said anything about CGI? All we know for sure is that there is some function called `param` and it takes a string as a parameter. If I was going to make the huge assumption that we're talking about the `param` function from CGI.pm then my first guess would be that a control called "search_string" would be a textbox not a checkbox. And besides, a CGI program should never make assumptions about the form that calls it. The query might come from a faked up form that has completely different controls on it. Or it might be a query that was built from scratch by a Perl script using LWP and have half of the required parameters missing. You're making an awful lot of assumptions here. -- <http://www.dave.org.uk> "The first rule of Perl club is you do not talk about Perl club." -- Chip Salzenberg	[reply]
Re5: Lexical variables question by dragonchild (Archbishop) on Aug 12, 2003 at 16:35 UTC