Algorithm for joining e.g. an array of strings

Question

I have wondered for some time, what a nice, clean solution for joining an array of strings might look like. Example: I have [\"Alpha\", \"Beta\", \"Gamma\"] and want to join

Answer 1

join() in Perl:

use List::Util qw(reduce);

sub mjoin($@) {$sep = shift; reduce {$a.$sep.$b} @_ or ''}

say mjoin(', ', qw(Alpha Beta Gamma));
# Alpha, Beta, Gamma

Or without reduce:

 sub mjoin($@) 
 {
   my ($sep, $sum) = (shift, shift); 
   $sum .= $sep.$_ for (@_); 
   $sum or ''
 }