Re: form parsing

Your code won't work, and neither will any of the responses so far, for the simple matter that $cgi->param doesn't return an lvalue!

Try this instead:

for my $p (qw(field1 field2)) {
  local $_ = $cgi->param($p);
  s/\*//g; # or tr/*//d;
  $cgi->param($p, $_); # set it back
}
[download]

-- Randal L. Schwartz, Perl hacker

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Re (tilly) 2: form parsing by tilly (Archbishop) on Oct 09, 2001 at 19:24 UTC
Now that we have somewhat functional code, it is still broken for two reasons. The first has to do with CGI's attempts to overload the param function with every possible behaviour. What happens if your form has an input variable named "-name"? The second has to do with Perl's list versus scalar context. What happens if your form sent back multiple values with the same name? Here is more robust code, using the functional interface (easily translated into the OO interface): `foreach my $name (param()) { my @values = param($p); s/\*//g foreach @values; param( -name=>$name, -values=>\@values ); }` [download] And people wonder why I prefer to avoid creating highly magical polymorphic interfaces? Note between merlyn and myself in 8 lines of code, with 5 different invocations of the param function, no two of them used the same part of the possible interface! (This is even true if you don't count the OO vs functional invocation issue.) People handle context pretty well, true, but there is a limit beyond which people start having problems. And when you mess up for this reason, it isn't very obvious that you did mess up, or what you did wrong!	[reply] [d/l]

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Re (tilly) 2: form parsing
by tilly (Archbishop) on Oct 09, 2001 at 19:24 UTC

The first has to do with CGI's attempts to overload the param function with every possible behaviour. What happens if your form has an input variable named "-name"?

The second has to do with Perl's list versus scalar context. What happens if your form sent back multiple values with the same name?

Here is more robust code, using the functional interface (easily translated into the OO interface):

foreach my $name (param()) {
  my @values = param($p);
  s/\*//g foreach @values;
  param( -name=>$name, -values=>\@values );
}
[download]

merlyn

[reply]
[d/l]