First, please make sure posted code compiles. Ignoring your pseudocode, you are missing a sigil on line 16 and a comma on line 22 and a curly bracket on line 31. See How do I post a question effectively?.

If a defined condition is sufficient (rather than exists), then you can easily perform the check with a grep and Slices: 

if(grep defined, @line{@{$new{a}}}) #need this condition

[download]
Otherwise, it's probably easiest to loop over the array ref: 
my $seen = 0;
for my $val (  @{$new{a}} ) {
    $seen++ if exists $line{$val};
}
if($seen) {#need this condition
    do something
} else {
    do something
}

[download]

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: Check if keys of hash is values of another hash! by kennethk
in thread Check if keys of hash is values of another hash! by stmadalli

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