detecting-languages

<!-- AI-RULEZ :: GENERATED FILE — DO NOT EDIT Content-Hash: blake3:70b679986812101189d1165f8f97d0a057d94d950920f1fff75724636e88291e Source-Hash: blake3:70559811033def67b9afc84aff0b0dd18329e8b04263cffeca7336545e95ab3c Schema-Version: v1 --> # Detecting languages tree-sitter-language-pack maps a file to one of 371 supported languages. Detection works from a file path, a bare extension, or — via the SDK — the file content itself. ## On the CLI: detection is implicit There is no standalone `ts-pack detect` command. `parse` and `process` auto-detect the language from the file extension and act on it: ```bash ts-pack parse src/app.ts # detects "typescript", parses ts-pack process app.py # detects "python", extracts ``` When detection fails (no extension, ambiguous, or stdin), pass `--language`: ```bash cat snippet | ts-pack parse - --language go ``` To check whether a language name is supported and cached without parsing anything, use `list` and `info`: ```bash ts-pack list --filter type # languages whose name contains "type" ts-pack list --manifest # every language in the remote manifest ts-pack info typescript # is it known? is it downloaded? cache path? ``` ## In the SDK: explicit detection The core exposes three detection functions, including content-based detection that the CLI does not surface: | Function | Detects from | | -------- | ------------ | | `detect_language_from_path(path)` | Full path (uses the extension). | | `detect_language_from_extension(ext)` | A bare extension like `"rs"`. | | `detect_language_from_content(content)` | Raw source text — no path needed. | Each returns the language name or null/None when no grammar matches. ### Python ```python from tree_sitter_language_pack import ( detect_language_from_path, detect_language_from_extension, detect_language_from_content, ) detect_language_from_path("src/app.py") # "python" detect_language_from_extension("rs") # "rust" detect_language_from_content(open("x").read()) # from the shebang line, if present ``` ### Node.js / TypeScript ```typescript import { detectLanguageFromPath, detectLanguageFromContent } from "@xberg-io/tree-sitter-language-pack"; const lang = detectLanguageFromPath("src/app.ts") ?? detectLanguageFromContent(source); ``` ## Choosing CLI vs SDK - Path or extension is enough, one-shot → just run `ts-pack parse`/`process` and let it auto-detect. - Only raw content (a pasted snippet, a stream, a file with no extension) → use the SDK's `detect_language_from_content`, then pass the result as `--language` to the CLI if needed. ## When to reach for the other skills Once the language is known, hand off to `parsing-source` (syntax tree) or `extracting-code-structure` (metadata). To see or prefetch the parser for a detected language, see `managing-parsers`.