Removes and returns thefirst element of an array. This shortens the array by one and moves everything down.
my @arr = ('cat', 'dog');my $item = shift(@arr); # 'cat'# @arr is now ('dog');Returnsundef if the array is empty.
Note:shift may also returnundef if the first element in the array isundef.
my @arr = (undef, 'two', 'three');my $item = shift(@arr); # undefIf ARRAY is omitted,shift operates on the@ARGV array in the main program, and the@_ array in subroutines.shift will operate on the@ARGV array ineval STRING,BEGIN {},INIT {},CHECK {} blocks.
Starting with Perl 5.14, an experimental feature allowedshift to take a scalar expression. This experiment has been deemed unsuccessful, and was removed as of Perl 5.24.
See alsounshift,push, andpop.shift andunshift do the same thing to the left end of an array thatpop andpush do to the right end.
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