In a standard Perl hash, a key can only have one value. (Though that value could be a reference to an array.)

# checking if this key-value pair exists
my ($key, $value) = ("foo", "123");

# ... in this hash
my %hash = (
  foo => "123",
  bar => "456",
);

if (exists $hash{$key} and $hash{$key} eq $value) {
  print "key-value pair exists\n";
}

[download]
perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

In reply to Re: Check if hash key value pair is defined by tobyink
in thread Check if hash key value pair is defined by reaper9187

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