How to Count Number of Occurrences of a Given Character in a String

How to Count Number of Occurrences of a Given Character in a String(pythonpips.com)

4 points by vaibhavmule 7 years ago

hannofcart 7 years ago |

How did this make it to HN front-page? Curious.

minimaxir 7 years ago | |

The weekend HN algorithm is very weird and frustrating.

That method doesn't really make sense, you could easily reuse an existing one: e.g. in JS: str.match(RegExp(char, 'g'))?.length, or [...str].filter(c => c === char).length

Someone 7 years ago | |

That call allocates a regular expression and, even ignoring that allocation, will struggle to be as fast as the count call.

(On top of that, I think it’s buggy. It won’t count character occurrences if char is a special character such as ‘^’ or ‘.’)