My offering (similar to above): 

use strict;

my @arr = qw(a b c d c e f);
insert_after_first(\@arr, "c", "x");

sub insert_after_first
{
    my $arr = shift;
    my $before = shift;
    my @new = @_;

    @$arr = map { 
        defined $before && $_ eq $before ? 
            do { $before = undef; @new } :
            $_
    } @$arr
}

use Data::Dumper;
print Dumper(\@arr);

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In reply to Re: Inserting an element into an array after a certain element by Tanktalus
in thread Inserting an element into an array after a certain element by saintmike

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