Re: Check user input - reimplementation

 $checks{'data'} =~ s/\s+/ /g;
 # remove leading and trailing blanks
 $checks{'data'} =~ s/^\s+//;
 $checks{'data'} =~ s/\s+$//;
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I'd do this in reverse order, so that you aren't substituting in a space that you're later going to remove. That's just a tiny amount of extra work. If the spaces are really spaces and not tabs, you can squeeze them using tr/ //s instead of s/\s+/ /g.

$checks{'regex'} = $checks{'regex'} ? $checks{'regex'} : $default;
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The common idiom for this is

$checks{'regex'} ||= $default;
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but be sure you mean that all false values should be replaced with default. You may have meant, instead

exists($checks{'regex'}) or $checks{'regex'} = $default;
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I note that regex is really expected to be a character class. It would be simple to take a real regex (qr// style) instead.

The PerlMonk tr/// Advocate

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Re: Re: Check user input - reimplementation by kiat (Vicar) on Dec 15, 2003 at 23:25 UTC
Thanks, Roy! I'd do this in reverse order, so that you aren't substituting in a space that you're later going to remove. That's just a tiny amount of extra work. You mean like this? `$checks{'data'} =~ s/\s+$//; $checks{'data'} =~ s/^\s+//; $checks{'data'} =~ s/\s+/ /g;` [download] Okay so `$checks{'regex'} \|\|= $default;` [download] is the same as `$checks{'regex'} = $checks{'regex'} ? $checks{'regex'} : $default;` [download] But what does the following do? `exists($checks{'regex'}) or $checks{'regex'} = $default;` [download]	[reply] [d/l] [select]
Re^3: Check user input - reimplementation by Roy Johnson (Monsignor) on Dec 16, 2003 at 21:26 UTC
You mean like this? Yes. `A \|\|= D` is, in general, the same as `A = A ? A : D` without all the repetition. Each assigns to A itself if A is true, and D if it is not true. The `exists` check is the same as `$check{'regex'} = $default unless exists($checks{'regex'})` [download] which is to say, it determines whether there a value has been assigned to `$checks{'regex'}`, and if not, it assigns the default value. Even if the value is false or undefined, `exists` returns true. The PerlMonk `tr///` Advocate	[reply] [d/l] [select]