Python Rocks (Perl Sucks)

Arg! Reading this in perl will make you scream, even if you know and love perl:

my @subgroup = (scalar(@{$group}) > $maxNumInSubgroup) ?
    @{$group}[0..($maxNumInSubgroup-1)] :
    @{$group};

First, I hate the way perl doesn’t treat every variable as equals. Why can’t everything just be a ref like in Python? Because of this, you have to worry about dereferencing, which makes nobody’s code beautiful. Even when you try to be consistent (as the author above is, thankfully), you still have to know about the other five or six methods of dereferencing.

Aside from that, Python’s indexing is one of its biggest strengths because it is consistent and beautiful. The above translated into Python:

subgroup = group[:maxNumInSubgroup]

Note that the resulting subgroup will not exceed the size of group, even if group has less items than maxNumInSubgroup.

Note that you have no “-1″‘s to get the array the right size.

Note also the absence of casts. Perl’s scalar cast on a list is one of the most wrong-headed decisions of all time. If I wanted to know the length of an array, I would ask for it explicitly. Of course, I hardly ever care what the length of an array is.

One more benefit… count the number of times you had to write “group” and “maxNumInSubgroup” in the perl and Python examples. Since you only had to write it once in Python, you can substitute the variable name for the expression that gave you the value in the first place. For example, compare the following two code samples:

Perl:

my $maxNumInSubgroup = pageSize/3 + 5;
my $group = getGroup(param1, param2);
my @subgroup = (scalar(@{$group}) > $maxNumInSubgroup) ?
    @{$group}[0..($maxNumInSubgroup-1)] :
    @{$group};

Python:

subgroup = getGroup(param1, param2)[:pageSize/3+5]

Not having to be repetitive means you don’t have to come up with new temporary variable names when they aren’t really necessary. It also reduces the complexity and length of your code.

Python wins. Perl loses.