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It will work fine for sub parameters. You can provide a list of keys as a second parameter to lock_keys:

sub whatever { my %params = @_; lock_keys %params, qw/ key1 key2 key3 /; say "Got key1" if $params{key1}; # ok say "Got key2" if $params{key2}; # ok say "Got key3" if $params{keye}; # Oops - BOOM! } whatever key2 => $value2; whatever keyq => $value1; # Hash has key 'keyq' which is not in the ne +w key set

For example, I use the following for parsing command-line options in my scripts:

use Getopt::Long qw/:config bundling/; use Hash::Util qw/ lock_keys /; our %OPT; my @OPT_SPEC = qw/ help|h version noact|no-act|dry-run DEBUG output|o= +s /; GetOptions \%OPT, @OPT_SPEC or ($OPT{help} = 1); lock_keys(%OPT, map /^(\w+)/, @OPT_SPEC);

Update 2: A diligent Anonymous monk actually tested this code (actually executing proposed code - what a concept) and pointed out that the initial lock_keys suggestion is sufficient. Updated the comments in the code above to reflect this.

Update: Add example where lock_keys is not quite sufficient... One could solve this in a couple ways without changing how whatever is called: Anonymous monk make all this unnecessary

# Option 1: use Params::Validate # Option 2: sub whatever { my @param_keys = qw/ key1 key2 key3 /; my %params = @_; $params{$_} //= undef for @param_keys; die "Invalid usage" if @param_keys != (keys %params); lock_keys %params; # ... } # Option 3: sub whatever { my %expected_params = map +($_,1), qw/ key1 key2 key3 /; my %params = @_; for (keys %params) { die "whatever: Unexpected named parameter $_" unless exists $e +xpected_params{$_}; } lock_keys %params, keys %expected_params; # ... }

Good Day,
    Dean


In reply to Re^4: Benifits of using hash rather than number of variables? by duelafn
in thread Benifits of using hash rather than number of variables? by tart

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