#delete EXPR

Deletes the specified key(s) and their associated values from a hash. For each key, returns the deleted value associated with that key, or the undefined value if there was no such key. Deleting from $ENV{} modifies the environment. Deleting from a hash tied to a DBM file deletes the entry from the DBM file. (But deleting from a tie()d hash doesn't necessarily return anything.)

The following deletes all the values of a hash:

    foreach $key (keys %HASH) {
	delete $HASH{$key};
    }

And so does this:

delete @HASH{keys %HASH}

(But both of these are slower than just assigning the empty list, or using undef().) Note that the EXPR can be arbitrarily complicated as long as the final operation is a hash element lookup or hash slice:

delete $ref->[$x][$y]{$key};
delete @{$ref->[$x][$y]}{$key1, $key2, @morekeys};

Perldoc Browser is maintained by Dan Book (DBOOK). Please contact him via the GitHub issue tracker or email regarding any issues with the site itself, search, or rendering of documentation.

The Perl documentation is maintained by the Perl 5 Porters in the development of Perl. Please contact them via the Perl issue tracker, the mailing list, or IRC to report any issues with the contents or format of the documentation.