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

In reply to Re: Re3: Lexical variables question by davorg
in thread Testing for filled-in box with CGI::param() ? by Anonymous Monk

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