lrl1997:

A hash table lets you get a value given its name. So you don't need the second loop: You can use the exists function (see perldoc -f exists ) to check if the key is in the other hash.)

$ cat t
my %h = (a=>1, b=>2, c=>3);

print "a ", exists($h{a}) ? "exists" : "does not exist", "\n";
print "c ", exists($h{c}) ? "exists" : "does not exist", "\n";
print "f ", exists($h{f}) ? "exists" : "does not exist", "\n";

$ perl t
a exists
c exists
f does not exist

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...roboticus

When your only tool is a hammer, all problems look like your thumb.

In reply to Re: how to loop through hash tables more efficiently by roboticus
in thread updated_again: how to loop through hash tables more efficiently by lrl1997

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