local $/;                   # undef $/ so we glob data in
$data = <DATA>;             # get all our data as a string
$data =~ s|//.*\n|\n|g;     # strip single line comments
$data =~ s|/\*.*?\*/||gs;   # strip multi-line comments
$data =~ s|^\s*\n||gm;      # strip blank lines
$data =~ s|^\s+||gm;        # strip leading whitespace
$data =~ s|\s+$||gm;        # strip trailing whitespace

# do the magic and split into functions
@functions = split /(?=\bfunction\s)/, $data;
# pudding proof
print "$_ ---\n" for @functions;


__DATA__
var answer = 42;  // just because

function 1 {
  blah // comment;
}

/* this function is no good
function 2 {
  blah
} */

function 3 {
  if (functionvar){   // var name not function keyword 
  // do the blah stuff
  }
}

/* this is 
another comment
*/

function 4 {
  just another perl hacker
}