I once had a web site
on which one could search
for all sorts of things
(as long as they’re strings)

The items had titles
and content and more
so the search used a regex
to help you explore

We had an idea
we gave it a try
let’s help you find more
we’ll add synonyms galore

We tacked on those words
to the end of the regex
and straight to production
(we didn’t have stress tests)

And lo and behold
the site all but crashed
so many timeouts
we all were abashed

The change was reverted
and there we sat hurted
trying to think
what brought us to this brink

We researched those regexes
and guess what we found:
you should compile them first
if you want them around

So try that we did
and it didn’t work
the site was still slow
we hoped it’s a quirk

We tried many things
we were all stressing
until we decided
it’s time to start testing!

We drew up some schemes
for searching multiple words
and what a surprise
we saw with our eyes

String.Find()
was 1000 times faster
than all of those regexes
which caused the disaster

We learned our lesson
I hope you did too
regexes are evil
except for a few

If your regex is simple
just put it away
you’re probably wasting
your time anyway

All of us know
the truth’s where it’s at
in most of the cases
YOU DON’T NEED A REGEX FOR THAT

P.S.
Please excuse my bad rhymes and rhythm, I get paid to write software. Not poetry.

Lisp

There once was a time bygone,
Way back in computing’s dawn.
The language was Lisp,
Its functions were crisp,
But its parentheses went on and on and on.

C

There once was a language named C,
Made by Thompson and Ritchie.
But it didn’t take a smart aleck,
To screw up a malloc,
For everyone to segfault and flee.

C++

Then came a language after C,
That was supposed to set us all free.
Objects were the fuss,
For this language called C++.
But it was just a fancier way to crash your PC.

Perl

There once was a language named Perl,
That Larry Wall thought would take over the world.
But the syntax was homely,
And often write-only,
And reading your code would make you hurl.

Python

Python was a language for you and for me
It was simple and clean, but slow we agree.
But that was ok,
We loved it anyway.
Until it went from version 2 to version 3.

PHP

There once was a language without any direction,
It lacked thought, and planning, and any affection.
PHP was insane,
And to save you from your pain,
You would need morphine in your SQL injection.

Java

There once was a great reception,
When Java had its conception.
For many fell in love,
But none could rise above,
When they encountered a null pointer exception.

JavaScript

JavaScript was made for the masses,
It lacked types, and modules, and classes.
But it became quite the giant,
Because it ran on server and client,
Until it crashed both, despite 100 test passes.

Ruby

Then came the wind to our sails,
In a language that every hipster hails.
Its name was Ruby,
It made an expert from a newbie,
Until it got traffic and it fell off the rails.

Go

And when Ruby went over the hill,
Go came in for the kill.
It seemed so fast,
But oh at long last,
We all got tired of err != nil.