On: Ask HN: What's the most valuable thing you can learn in an hour?

[agungsukma]

Yes, regular expression. Saves me from lines of substr, split, join, etc.

[enraged_camel → agungsukma]

Eh, I always use substr, split and so on if possible. They make the code way easier to read than with a regex.

[Izkata → enraged_camel]

It really depends on what you're doing, and at least being aware of what regex can do will help with deciding which is better for a given situation.

For example, I remember once replacing a buggy 3-4 lines of python based on split/etc with a single regex: match all \d+ (it was for extracting IDs from a user-input string)