Python-Perl cheatsheet


what Python Perl notes
null type None undef not exactly identical
String concatenation "py"+"thon" "pe"."rl"
declare a list [1,2,3] (1,2,3) note that arrays contain only scalars! (1,2, (3,4), 5) becomes (1,2,3,4,5)
array length len(array) $#array + 1 Python returns the length of array. Perl gives me the index of the last element.
range(1,100) (1..100)
create a list from whitespaced values "fred barney wilma dino".split() qw( fred barney wilma dino); You can use separators others than parenthesis, e.g. qw ! fred barney wilma dino !
multiple assignment fred, barney, dino = "flintstone", "rubble", None ($fred, $barney, $dino) = ("flintstone", "rubble", undef);
array concatenation a+b (@a, @b) you can also mix like (@a, 3, @b, undef)
array.append(item) push @array, item; See also Perl's unshift() for attaching to the front of array
val = array.pop() val = pop @array, item; See also Perl's shift() for removing from the front of array
List iteration for item in array foreach $item (@array) Note that $item is the real element of @array, so if you modify $item, you modify the array content