With the code and data you've shown, I cannot reproduce your problem:

#!perl -w
use strict;

my $key="5    10    14    16    17    20    25    26    38  1  42    4
+7    54";
my $substr = " 1 ";
my @newarray= $key;
foreach $key ( @newarray ) {
    if (index($key, $substr) != -1) {
        print "\nExist (substr)"
    };
    if ($key =~ /\Q$substr\E/) {
        print "\nExist (RE)"
    };
    if ($key =~ /\s+1\s+/) {
        print "\nExist (whitespace)"
    };
}
__END__

>perl -w tmp.pl

Exist (substr)
Exist (RE)
Exist (whitespace)

[download]

Maybe your data in $key really has tabs in it, but you are searching for blanks?

In reply to Re: Foreach loop by Corion
in thread Foreach loop by PetreAdi

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