Perl 5 version documentation

unshift

Perl functions A-Z | Perl functions by category | The 'perlfunc' manpage
  • unshift ARRAY,LIST

    Does the opposite of a shift. Or the opposite of a push, depending on how you look at it. Prepends list to the front of the array and returns the new number of elements in the array.

    1.     unshift(@ARGV, '-e') unless $ARGV[0] =~ /^-/;

    Note the LIST is prepended whole, not one element at a time, so the prepended elements stay in the same order. Use reverse to do the reverse.

    Starting with Perl 5.14, an experimental feature allowed unshift to take a scalar expression. This experiment has been deemed unsuccessful, and was removed as of Perl 5.24.