Strange. I was able to duplicate your problem (by adding   use CGI qw(:standard); to the top of that fragment). The change I offer fixes the problem, at least does when I try it. What, exactly, does your code fragment look like when you try it?

Mine looks like this:

C:\test>type test.pl
use CGI qw(:standard);
# my %params =  map ($_ => param('$_'),param());
my %params = map {$_ => param($_)} param();
print '-->' . $params{'listname'}. '<--' . "\n";

C:\test>perl test.pl listname=foo bar
-->foo<--
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The problem is with the single quote around '$_', which tells param to look for an exact match of '$_', not an element from the param list. If you take away the single quotes from the $_, the code should work fine.

The reason for the code to display "bar" for "listname" is because the hash was not correctly constructed. The failed mapping created a hash: listname=>bar as a side effect.

Hrmm, mine looks very similar.

use strict;
use CGI qw/:standard/;
use DBI;
use Mail::Sendmail;
use MIME::Lite;

my $q = CGI::new();

my %params =  map {$_ => param('$_')} param();
print '-->' . $params{'listname'}. '<--' . "\n";
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I am running this on a debian box however you seem to be using windows, i wonder if this is contributing as our code looks very similar.

Neil Archibald
- /dev/IT -

use CGI qw/:standard/;
my %params =  map { $_ => scalar param($_) } param();
print '-->' . $params{'listname'}. '<--' . "\n";
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1. You're trying to use A => B as an expression for map, which doesn't work, as "=>" is actually a comma. So map only saw the "A" as the expression, and the "B" as the first item of the list fed to it.
2. You used single quotes around "$_" which made CGI.pm look for the parameter "'$_'", literally, which doesn't exist. Combine that with...
3. You used param() in a list context, which for a non-existing parameter produces an empty list. "scalar" fixes that.