Correct, easy to "remember this per iteration" is with scalar value of grep{}!

Code below shows one line creation of a hash with values of array to be compared against. Then use of scalar value of grep which is # of matches which is used in logical sense, not numeric.

Perl grep() is most often used in a "filter" sense, but it does have a scalar value. 

#!/usr/bin/perl -w
use strict;

my @test_a = qw (a b c d e);
my @test_b = qw (a b c d e);
my @test_c = qw (a b c d f);

my %standard = map{$_ => 1}@test_a;

if (grep{!$standard{$_}}@test_b)
{
   print "FAIL test_b .. not all b in a\n";
}
else
{ 
   print "PASS test_b .. all b in a\n";
}

if (grep{!$standard{$_}}@test_c)
{
   print "FAIL test_c .. not all c in a\n";
}
else
{ 
   print "PASS test_c .. all c in a\n";
}
__END__
PRINTS:
PASS test_b .. all b in a
FAIL test_c .. not all c in a

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In reply to Re^2: if else statement check an array by Marshall
in thread if else statement check an array by sqspat

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