Simple Code Tasks Should Be Simple

manchicken profile image Michael D. Stemle, Jr. ・2 min read

I frequently see people do simple things in the most complicated ways with dynamic languages. I suspect much of this is a carry-over from how we teach algorithms and programming in universities. If you want your code to be readable, and you want it to be maintainable long-term, then simple code tasks should be simple.

Merging Two Lists

This is simple. You've got a list of fruits, and a list of vegetables, and you want to merge them into a list called "produce."

In Perl:

my @fruits = qw/apple banana mango/;
my @veggies = qw/broccoli asparagus spinach/;

In JavaScript:

const fruits = ['apple', 'banana', 'mango']
const veggies = ['broccoli', 'asparagus', 'spinach']

Some folks will want to use iteration, or even a push() function of some sort here, but neither is necessary. A simple assignment statement will work just fine.

In Perl:

my @produce = (@fruits, @veggies);

In JavaScript:

const produce = [...fruits, ...veggies];

Not very impressive, I know, but watch what happens when I do the same thing with associative arrays (a.k.a. Objects, a.k.a. hashes). Now we're going to have produce items, with their colors.

In Perl:

my %fruits = (
  apple  => 'red',
  banana => 'yellow',
  mango  => 'light-orange');
my %veggies = (
  broccoli  => 'green',
  asparagus => 'green',
  spinach   => 'green');

my %produce = (%fruits, %veggies);

In JavaScript:

const fruits = {
  apple:  'red',
  banana: 'yellow',
  mango:  'light-orange'}
const veggies = {
  broccoli:  'green',
  asparagus: 'green',
  spinach:   'green'}

const produce = {...fruits, ...veggies};

It's super cool to have slick code that does neat things, but when it comes to squishing data together keeping things simple is always better.

One Exception: When you're using JavaScript, the spread operator (...) is limited to the maximum limit supported by Function.apply(), which (as of the time of this post) is 65,536 total values.

Anyway, I had fun writing this and I hope that your code brings you joy.


Editor guide

This is why you will hear experienced Perlers (Perlizens?) insist that an array is not a list. If you understand that an array is a list interpreted in numeric indexed order and a hash is a list interpreted in pairwise key value fashion, then you are more likely to perform "list" operations when beneficial. I think the Perl literature needs to do more than it already does to make a "list" a real, live actual data structure, distinct from the array and hash "storage" of lists.


What does this semantic difference mean for those writing code?


It means they realize they can do list-y type things and not resort to loops, i.e. the answer to your followup question is your article. :-)

Or, more precisely, if the semantic difference was more distinctly taught, you wouldn't have had to write your article.

Yeah, most dynamic languages seem to have this same difference. I think that for beginners it is semantics, but for those who are starting to come into their own in their coding practice it's a super important concept to understand.

Thanks for this contribution!