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

In Perl, I just use the join command:

$ echo "Alpha
Beta
Gamma" | perl -e 'print(join(", ", map {chomp; $_} <> ))'
Alpha, Beta, Gamma

(The map stuff is mostly there to create a list.)

In languages that don't have a built in, like C, I use simple iteration (untested):

for (i = 0; i < N-1; i++){
    strcat(s, a[i]);
    strcat(s, ", ");
}
strcat(s, a[N]);

Of course, you'd need to check the size of s before you add more bytes to it.

You either have to special case the first entry or the last.