How the Code Fixer Detects Your Programming Language
Before CodeLens AI can explain or repair a snippet, it first has to work out what language it's looking at. Nobody wants to select a language from a dropdown every time, so detection needed to be automatic and fast.
Pattern signals
The detector looks for a handful of strong signals rather than trying to fully parse the code:
- Opening tags like
<?phpor<!DOCTYPE html>are near-certain giveaways. - Keyword density — words like
def,function,const,public class, orSELECT ... FROMeach point to a different language family. - Punctuation shape — heavy use of curly braces and semicolons suggests C-family languages (JS, PHP, Java, C++); indentation-based blocks with no braces point toward Python.
- File-style hints — CSS selectors followed by declaration blocks, or HTML tag nesting, are distinctive enough to flag on their own.
Why this matters for fixing code
Getting the language right matters because the fix suggestions and explanation style change completely depending on context — a missing semicolon means something different in JavaScript than a missing colon does in Python. Once the language is identified, the snippet is handed off with the right context so the explanation and any suggested fix actually make sense for that language's rules.
Want to see it in action? Head over to the Code Tool and paste in a snippet — the detected language shows up before anything else.