in reply to check parameters

Build the pattern first, then use it. 

my $pattern ="(".join('|', @{$opts->{params}}).")";
if (!grep { /^$pattern/i } keys %$format)
{
    ...

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Re^2: check parameters
by ag4ve (Monk) on Apr 08, 2013 at 14:26 UTC
    Ah, should've figured. Thanks that works. 
    if ("(".join('|', @{$opts->{params}}).")" and !grep { /^$_/i } keys %$
+format)

    [download]
    That looks aweful - is there a better way of doing this?
[reply]
[d/l]

      Untested:

      if (!grep { /^${\ (join '|', @{$opts->{params}}) }/i } keys %$format)

      [download]
      package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name
[reply]
[d/l]
      Ugh, actually something about that doesn't work.... It passes when it shouldn't :(
[reply]

        What is wrong with the code hdb gave you?

        That code does not have the problem your code has, so why are you not using it?

        As a hint, a string is always true in Perl. And your code simply constructs a string but never matches against it:

        ...
if ("(".join('|', @{$opts->{params}}).")" # This constructs a string
    and !grep { /^$_/i } keys %$format)   # and this matches $_ agains
+t itself
...

        [download]
[reply]
[d/l]
        This should fail and doesn't: 
        use strict;
use warnings;

use Pod::Usage;

my $format = {
    abc => 1,
    bar => 1,
    fii => 1,
    wee => 1,
};

my $opts;
$opts->{params} = ["a", "fa"];

my $str = "(".join('|', @{$opts->{params}}).")";
if (!grep { /^$str/i } keys %$format)
{
  pod2usage( -verbose => 0, -output => \*STDERR,
          -msg => "$0 bad parameter difinition used [" . join(", ", so
+rt {$a cmp $b} @{$opts->{params}}) . "].\n" .
                  "Possible parameters are: " . 
                  join(", ", sort {$a cmp $b} keys %$format) . "\n");
}

print "1\n";

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[reply]
[d/l]

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