Tokenize a string

Separate the string "Hello,How,Are,You,Today" by commas into an array so that each index of the array stores a different word. Display the words to the 'user', in the simplest manner possible, separated by a period. To simplify, you may display a trailing period.

Perl

Interpreter: Perl any 5.X

As a one liner without a trailing period, and most efficient way of doing it as you don't have to define an array.

print join('.', split(/,/, "Hello,How,Are,You,Today"));

If you needed to keep an array for later use, again no trailing period

my @words = split(/,/, "Hello,How,Are,You,Today");
print join('.', @words);

If you really want a trailing period, here is an example

my @words = split(/,/, "Hello,How,Are,You,Today");
print $_.'.' for (@words);

Ruby

    string = "Hello,How,Are,You,Today".split(',')
    string.each do |w|
         print "#{w}."
    end

Tcl

Generating a list form a string by splitting on a comma:

 split string ,

Joining the elements of a list by a period:

 join list .

Thus the whole thing would look like this:

 puts [join [split "Hello,How,Are,You,Today" ,] .]

If you'd like to retain the list in a variable with the name "words", it would only be marginally more complex:

 puts [join [set words [split "Hello,How,Are,You,Today" ,]] .]