# go_sm URL: /api/lexers/go_sm/ Section: lexers -------------------------------------------------------------------------------- go_sm - Rosettes window.BENGAL_THEME_DEFAULTS = { appearance: 'light', palette: 'brown-bengal' }; window.Bengal = window.Bengal || {}; window.Bengal.enhanceBaseUrl = '/rosettes/assets/js/enhancements'; window.Bengal.watchDom = true; window.Bengal.debug = false; window.Bengal.enhanceUrls = { 'toc': '/rosettes/assets/js/enhancements/toc.632a9783.js', 'docs-nav': '/rosettes/assets/js/enhancements/docs-nav.57e4b129.js', 'tabs': '/rosettes/assets/js/enhancements/tabs.aac9e817.js', 'lightbox': '/rosettes/assets/js/enhancements/lightbox.1ca22aa1.js', 'interactive': '/rosettes/assets/js/enhancements/interactive.fc077855.js', 'mobile-nav': '/rosettes/assets/js/enhancements/mobile-nav.d991657f.js', 'action-bar': '/rosettes/assets/js/enhancements/action-bar.d62417f4.js', 'copy-link': '/rosettes/assets/js/enhancements/copy-link.7d9a5c29.js', 'data-table': '/rosettes/assets/js/enhancements/data-table.1f5bc1eb.js', 'lazy-loaders': '/rosettes/assets/js/enhancements/lazy-loaders.a5c38245.js', 'holo': '/rosettes/assets/js/enhancements/holo.ee13c841.js', 'link-previews': '/rosettes/assets/js/enhancements/link-previews.8d906535.js' }; (function () { try { var defaults = window.BENGAL_THEME_DEFAULTS || { appearance: 'system', palette: '' }; var defaultAppearance = defaults.appearance; if (defaultAppearance === 'system') { defaultAppearance = (window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches) ? 'dark' : 'light'; } var storedTheme = localStorage.getItem('bengal-theme'); var storedPalette = localStorage.getItem('bengal-palette'); var theme = storedTheme ? (storedTheme === 'system' ? defaultAppearance : storedTheme) : defaultAppearance; var palette = storedPalette ?? defaults.palette; document.documentElement.setAttribute('data-theme', theme); if (palette) { document.documentElement.setAttribute('data-palette', palette); } } catch (e) { document.documentElement.setAttribute('data-theme', 'light'); } })(); { "prerender": [ { "where": { "and": [ { "href_matches": "/docs/*" }, { "not": { "selector_matches": "[data-external], [target=_blank], .external" } } ] }, "eagerness": "conservative" } ], "prefetch": [ { "where": { "and": [ { "href_matches": "/*" }, { "not": { "selector_matches": "[data-external], [target=_blank], .external" } } ] }, "eagerness": "conservative" } ] } Skip to main content Magnifying Glass ESC Recent Clear Magnifying Glass No results for "" Start typing to search... ↑↓ Navigate ↵ Open ESC Close Powered by Lunr ⌾⌾⌾ DocumentationInfoAboutArrow ClockwiseGet StartedCodeHighlightingPaletteStylingStarburstExtendingFormattersNoteTutorialsBookmarkReferenceReleasesDevGitHubAPI Reference Magnifying Glass Search ⌘K Palette Appearance Chevron Down Mode Monitor System Sun Light Moon Dark Palette Snow Lynx Brown Bengal Silver Bengal Charcoal Bengal Blue Bengal List ⌾⌾⌾ Magnifying Glass Search X Close Documentation Caret Down Info About Arrow Clockwise Get Started Code Highlighting Palette Styling Starburst Extending Formatters Note Tutorials Bookmark Reference Releases Dev Caret Down GitHub API Reference Palette Appearance Chevron Down Mode Monitor System Sun Light Moon Dark Palette Snow Lynx Brown Bengal Silver Bengal Charcoal Bengal Blue Bengal Rosettes API Reference Caret Right Formatters html null terminal Caret Right Lexers _scanners _state_machine bash_sm c_sm clojure_sm cpp_sm css_sm csv_sm cuda_sm cue_sm dart_sm diff_sm dockerfile_sm elixir_sm gleam_sm go_sm graphql_sm groovy_sm haskell_sm hcl_sm html_sm ini_sm java_sm javascript_sm jinja_sm json_sm julia_sm kida_sm kotlin_sm lua_sm makefile_sm markdown_sm mojo_sm nginx_sm nim_sm perl_sm php_sm pkl_sm plaintext_sm powershell_sm protobuf_sm python_sm r_sm ruby_sm rust_sm scala_sm sql_sm stan_sm swift_sm toml_sm tree_sm triton_sm typescript_sm v_sm xml_sm yaml_sm zig_sm Caret Right Themes _mapping _palette _roles palettes _config _escape _formatter_registry _parallel _protocol _registry _types delegate rosettes Rosettes API ReferenceLexers ᗢ Caret Down Link Copy URL External Open LLM text Copy Copy LLM text Share with AI Ask Claude Ask ChatGPT Ask Gemini Ask Copilot Module lexers.go_sm Hand-written Go lexer using composable scanner mixins. O(n) guaranteed, zero regex, thread-safe. Language Support: Go 1.21+ syntax Raw strings (backtick literals) Runes (character literals) Imaginary numbers (1i, 3.14i) Channel operator (<-) Short variable declaration (:=) All standard operators Go-Specific Features: Exported Names: Go convention is that exported (public) names start with uppercase. The lexer detects this and classifies them as NAME_CLASS for visual distinction. Raw Strings: Backtick-delimited strings can span multiple lines and contain literal newlines without escaping. Imaginary Numbers: Numbers can have i suffix for complex literals. Performance: ~40µs per 100-line file (Go has simple, regular syntax). Thread-Safety: All lookup tables are frozen sets. Scanning uses local variables only. See Also: rosettes.lexers.rust_sm: Similar systems language lexer rosettes.lexers._scanners: Shared mixin implementations 1Class Classes GoStateMachineLexer 2 ▼ Go lexer using composable mixins. Go has clean, regular syntax making it one of the simpler lexers… Go lexer using composable mixins. Go has clean, regular syntax making it one of the simpler lexers. Token Classification: Declaration keywords: func, type, struct, interface, const, var Namespace keywords: import, package Constants: true, false, nil, iota Types: Primitive types (int, string, bool, etc.) Builtins: make, len, cap, append, etc. Special Handling: Exported names (starting with uppercase) → NAME_CLASS Raw strings (backticks) can span multiple lines Runes (character literals) use single quotes Methods tokenize 2 Iterator[Token] ▼ Tokenize Go source code. def tokenize(self, code: str, config: LexerConfig | None = None) -> Iterator[Token] Parameters Name Type Description code — config — Default: None Returns Iterator[Token] Internal Methods 1 ▼ _classify_word 1 TokenType ▼ Classify an identifier. def _classify_word(self, word: str) -> TokenType Parameters Name Type Description word — Returns TokenType ← Previous gleam_sm Next → graphql_sm List © 2026 Rosettes built in ᓚᘏᗢ { "linkPreviews": { "enabled": true, "hoverDelay": 200, "hideDelay": 150, "showSection": true, "showReadingTime": true, "showWordCount": true, "showDate": true, "showTags": true, "maxTags": 3, "includeSelectors": [".prose"], "excludeSelectors": ["nav", ".toc", ".breadcrumb", ".pagination", ".card", "[class*='-card']", ".tab-nav", "[class*='-widget']", ".child-items", ".content-tiles"], "allowedHosts": [], "allowedSchemes": ["https"], "hostFailureThreshold": 3 } } window.BENGAL_LAZY_ASSETS = { tabulator: '/rosettes/assets/js/tabulator.min.js', dataTable: '/rosettes/assets/js/data-table.js', mermaidToolbar: '/rosettes/assets/js/mermaid-toolbar.9de5abba.js', mermaidTheme: '/rosettes/assets/js/mermaid-theme.344822c5.js', graphMinimap: '/rosettes/assets/js/graph-minimap.ff04e939.js', graphContextual: '/rosettes/assets/js/graph-contextual.355458ba.js' }; window.BENGAL_ICONS = { close: '/rosettes/assets/icons/close.911d4fe1.svg', enlarge: '/rosettes/assets/icons/enlarge.652035e5.svg', copy: '/rosettes/assets/icons/copy.3d56e945.svg', 'download-svg': '/rosettes/assets/icons/download.04f07e1b.svg', 'download-png': '/rosettes/assets/icons/image.c34dfd40.svg', 'zoom-in': '/rosettes/assets/icons/zoom-in.237b4a83.svg', 'zoom-out': '/rosettes/assets/icons/zoom-out.38857c77.svg', reset: '/rosettes/assets/icons/reset.d26dba29.svg' }; Arrow Up -------------------------------------------------------------------------------- Metadata: - Word Count: 782 - Reading Time: 4 minutes