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Go API Reference

Go API Reference v1.9.1

Functions

DetectLanguageFromExtension()

Detect language name from a file extension (without leading dot).

Returns nil for unrecognized extensions. The match is case-insensitive.

Signature:

func DetectLanguageFromExtension(ext string) *string

Example:

result := DetectLanguageFromExtension("value")

Parameters:

Name Type Required Description
Ext string Yes The ext

Returns: *string


DetectLanguageFromPath()

Detect language name from a file path.

Extracts the file extension and looks it up. Returns nil if the path has no extension or the extension is not recognized.

Signature:

func DetectLanguageFromPath(path string) *string

Example:

result := DetectLanguageFromPath("value")

Parameters:

Name Type Required Description
Path string Yes Path to the file

Returns: *string


DetectLanguageFromContent()

Detect language name from file content using the shebang line (#!).

Inspects only the first line of content. If it begins with #!, the interpreter name is extracted and mapped to a language name.

Handles common patterns:

  • #!/usr/bin/env python3"python"
  • #!/bin/bash"bash"
  • #!/usr/bin/env node"javascript"

The -S flag accepted by some env implementations is skipped automatically. Version suffixes (e.g. python3.11, ruby3.2) are stripped before matching.

Returns nil when content does not start with #!, the shebang is malformed, or the interpreter is not recognised.

Signature:

func DetectLanguageFromContent(content string) *string

Example:

result := DetectLanguageFromContent("value")

Parameters:

Name Type Required Description
Content string Yes The content to process

Returns: *string


GetHighlightsQuery()

Get the highlights query for a language, if bundled.

Returns the contents of highlights.scm as a static string, or nil if no highlights query is bundled for this language.

Signature:

func GetHighlightsQuery(language string) *string

Example:

result := GetHighlightsQuery("value")

Parameters:

Name Type Required Description
Language string Yes The language

Returns: *string


GetInjectionsQuery()

Get the injections query for a language, if bundled.

Returns the contents of injections.scm as a static string, or nil if no injections query is bundled for this language.

Signature:

func GetInjectionsQuery(language string) *string

Example:

result := GetInjectionsQuery("value")

Parameters:

Name Type Required Description
Language string Yes The language

Returns: *string


GetLocalsQuery()

Get the locals query for a language, if bundled.

Returns the contents of locals.scm as a static string, or nil if no locals query is bundled for this language.

Signature:

func GetLocalsQuery(language string) *string

Example:

result := GetLocalsQuery("value")

Parameters:

Name Type Required Description
Language string Yes The language

Returns: *string


GetTagsQuery()

Get the tags query for a language, if bundled.

Returns the contents of tags.scm as a static string, or nil if no tags query is bundled for this language.

Signature:

func GetTagsQuery(language string) *string

Example:

result := GetTagsQuery("value")

Parameters:

Name Type Required Description
Language string Yes The language

Returns: *string


GetLanguage()

Get a tree-sitter Language by name using the global registry.

Resolves language aliases (e.g., "shell" maps to "bash"). When the download feature is enabled (default), automatically downloads the parser from GitHub releases if not found locally.

Errors:

Returns Error.LanguageNotFound if the language is not recognized, or Error.Download if auto-download fails.

Signature:

func GetLanguage(name string) (Language, error)

Example:

result, err := GetLanguage("value")
if err != nil {
    return err
}

Parameters:

Name Type Required Description
Name string Yes The name

Returns: Language

Errors: Returns error.


GetParser()

Get a Parser pre-configured for the given language.

This is a convenience function that calls get_language and configures a new parser in one step.

Errors:

Returns Error.LanguageNotFound if the language is not recognized, or Error.ParserSetup if the language cannot be applied to the parser.

Signature:

func GetParser(name string) (Parser, error)

Example:

result, err := GetParser("value")
if err != nil {
    return err
}

Parameters:

Name Type Required Description
Name string Yes The name

Returns: Parser

Errors: Returns error.


DetectLanguage()

Detect language name from a file path or extension.

This compatibility alias matches the pre-Alef Python binding API.

Signature:

func DetectLanguage(path string) *string

Example:

result := DetectLanguage("value")

Parameters:

Name Type Required Description
Path string Yes Path to the file

Returns: *string


AvailableLanguages()

List all available language names (sorted, deduplicated, includes aliases).

Returns names of both statically compiled and dynamically loadable languages, plus any configured aliases.

Signature:

func AvailableLanguages() []string

Example:

result := AvailableLanguages()

Returns: []string


HasLanguage()

Check if a language is available by name or alias.

Returns true if the language can be loaded (statically compiled, dynamically available, or a known alias for one of these).

Signature:

func HasLanguage(name string) bool

Example:

result := HasLanguage("value")

Parameters:

Name Type Required Description
Name string Yes The name

Returns: bool


LanguageCount()

Return the number of available languages.

Includes statically compiled languages, dynamically loadable languages, and aliases.

Signature:

func LanguageCount() int

Example:

result := LanguageCount()

Returns: int


Process()

Process source code and extract file intelligence using the global registry.

Parses the source with tree-sitter and extracts metrics, structure, imports, exports, comments, docstrings, symbols, diagnostics, and/or chunks based on the flags set in ProcessConfig.

Errors:

Returns an error if the language is not found or parsing fails.

Signature:

func Process(source string, config ProcessConfig) (ProcessResult, error)

Example:

result, err := Process("value", ProcessConfig{})
if err != nil {
    return err
}

Parameters:

Name Type Required Description
Source string Yes The source
Config ProcessConfig Yes The configuration options

Returns: ProcessResult

Errors: Returns error.


Init()

Initialize the language pack with the given configuration.

Applies any custom cache directory, then downloads all languages and groups specified in the config. This is the recommended entry point when you want to pre-warm the cache before use.

Errors:

Returns an error if configuration cannot be applied or if downloads fail.

Signature:

func Init(config PackConfig) error

Example:

if err := Init(PackConfig{}); err != nil {
    return err
}

Parameters:

Name Type Required Description
Config PackConfig Yes The configuration options

Returns: No return value.

Errors: Returns error.


Configure()

Apply download configuration without downloading anything.

Use this to set a custom cache directory before the first call to get_language or any download function. Changing the cache dir after languages have been registered has no effect on already-loaded languages.

Errors:

Returns an error if the lock cannot be acquired.

Signature:

func Configure(config PackConfig) error

Example:

if err := Configure(PackConfig{}); err != nil {
    return err
}

Parameters:

Name Type Required Description
Config PackConfig Yes The configuration options

Returns: No return value.

Errors: Returns error.


Download()

Download specific languages to the local cache.

Returns the number of requested languages available after the call. Already compiled or cached languages are included in the count.

Errors:

Returns an error if any language is not available in the manifest or if the download fails.

Signature:

func Download(names []string) (int, error)

Example:

result, err := Download(nil)
if err != nil {
    return err
}

Parameters:

Name Type Required Description
Names \[\]string Yes The names

Returns: int

Errors: Returns error.


DownloadAll()

Download all available languages from the remote manifest.

Downloads the platform bundle and extracts every library it contains. Languages that appear in the manifest but are absent from the bundle (e.g. grammars that failed to compile at release time) are silently skipped — they are not treated as an error.

Returns the total number of languages now available (statically compiled plus downloaded and cached).

Errors:

Returns an error if the manifest cannot be fetched or the bundle download fails.

Signature:

func DownloadAll() (int, error)

Example:

result, err := DownloadAll()
if err != nil {
    return err
}

Returns: int

Errors: Returns error.


DownloadGroup()

Download every language in a named group (e.g. "web", "data").

Groups are defined in the remote manifest and let you ensure a curated set of related grammars in one call instead of listing each name to download(). Already-cached languages are skipped.

Returns the total number of languages now available (statically compiled plus downloaded and cached).

Errors:

Returns an error if the manifest cannot be fetched, the group is unknown, or any constituent language fails to download.

Signature:

func DownloadGroup(name string) (int, error)

Example:

result, err := DownloadGroup("value")
if err != nil {
    return err
}

Parameters:

Name Type Required Description
Name string Yes The name

Returns: int

Errors: Returns error.


ManifestLanguages()

Return all language names available in the remote manifest (306).

Fetches (and caches) the remote manifest to discover the full list of downloadable languages. Use downloaded_languages to list what is already cached locally.

Errors:

Returns an error if the manifest cannot be fetched.

Signature:

func ManifestLanguages() ([]string, error)

Example:

result, err := ManifestLanguages()
if err != nil {
    return err
}

Returns: []string

Errors: Returns error.


DownloadedLanguages()

Return languages that are already downloaded and cached locally.

Does not perform any network requests. Returns an empty list if the cache directory does not exist or cannot be read.

Signature:

func DownloadedLanguages() []string

Example:

result := DownloadedLanguages()

Returns: []string


CleanCache()

Delete all cached parser shared libraries.

Resets the cache registration so the next call to get_language or a download function will re-register the (now empty) cache directory.

Errors:

Returns an error if the cache directory cannot be removed.

Signature:

func CleanCache() error

Example:

if err := CleanCache(); err != nil {
    return err
}

Returns: No return value.

Errors: Returns error.


CacheDir()

Return the effective cache directory path.

This is either the custom path set via configure / init or the default: ~/.cache/tree-sitter-language-pack/v{version}/libs/.

Errors:

Returns an error if the system cache directory cannot be determined.

Signature:

func CacheDir() (string, error)

Example:

result, err := CacheDir()
if err != nil {
    return err
}

Returns: string

Errors: Returns error.


Types

ByteRange

A byte range — start (inclusive) to end (exclusive).

Field Type Default Description
Start int Inclusive start byte offset.
End int Exclusive end byte offset.

ChunkContext

Metadata for a single chunk of source code.

Field Type Default Description
Language string Language name used to parse this chunk.
ChunkIndex int Zero-indexed position of this chunk within the file's chunk list.
TotalChunks int Total number of chunks the file was split into.
NodeTypes \[\]string nil Tree-sitter node kinds that appear at the top level of this chunk.
ContextPath \[\]string nil Hierarchical path of enclosing structural items (e.g., \["MyClass", "my_method"\]).
SymbolsDefined \[\]string nil Names of symbols defined within this chunk.
Comments \[\]CommentInfo nil Comments contained within this chunk.
Docstrings \[\]DocstringInfo nil Docstrings contained within this chunk.
HasErrorNodes bool Whether this chunk contains any tree-sitter error nodes.

CodeChunk

A chunk of source code with rich metadata.

Field Type Default Description
Content string The raw source text of this chunk.
StartByte int Inclusive start byte offset of this chunk in the original source.
EndByte int Exclusive end byte offset of this chunk in the original source.
StartLine int Zero-indexed start line of this chunk.
EndLine int Zero-indexed end line of this chunk.
Metadata ChunkContext Contextual metadata about this chunk.

CommentInfo

A comment extracted from source code.

Field Type Default Description
Text string The raw text content of the comment.
Kind CommentKind CommentKind.Line The kind of comment (line, block, or doc).
Span Span Source span covering the comment.
AssociatedNode *string nil Name of the syntax node this comment is directly associated with.

DataAttribute

An XML-style attribute attached to an Element node.

Populated only for DataNodeKind.Element; always empty for KeyValue and Sequence nodes.

Field Type Default Description
Name string Attribute name (e.g. "class", "href").
Value string Attribute value as a raw string (quotes stripped).
Span Span Source span covering the entire name="value" attribute token.

DataNode

A node in the hierarchical data tree produced by data-format extraction.

When ProcessConfig.data_extraction is true, ProcessResult.data is populated with a root DataNode whose children mirror the structure of the parsed file.

The kind field determines which other fields are meaningful:

kind key value attributes children
KeyValue key / mapping key / index leaf value empty nested map
Element XML tag name text content XML attrs child elements
Sequence positional index ("0") leaf value empty sub-items
Field Type Default Description
Kind DataNodeKind DataNodeKind.KeyValue Whether this node is a key/value pair, XML element, or sequence item.
Key *string nil Key, attribute name, tag name, or positional index ("0", "1", …). nil at the document root.
Value *string nil Leaf scalar value, if any. nil for containers (objects, arrays, XML elements with child elements).
Attributes \[\]DataAttribute nil Attributes on element-shape nodes (XML STag attributes). Empty for all other kinds.
Children \[\]DataNode nil Children for nested containers and XML element bodies.
Span Span Source span covering this node in the original source file.

Diagnostic

A diagnostic (syntax error, missing node, etc.) from parsing.

Field Type Default Description
Message string Human-readable description of the diagnostic.
Severity DiagnosticSeverity DiagnosticSeverity.Error Severity of the diagnostic.
Span Span Source span where the diagnostic was detected.

DocSection

A section within a docstring (e.g., Args, Returns, Raises).

Field Type Default Description
Kind string Section kind (e.g., "args", "returns", "raises").
Name *string nil Parameter or return value name, if applicable.
Description string Description text for this section.

DocstringInfo

A docstring extracted from source code.

Field Type Default Description
Text string The raw text of the docstring.
Format DocstringFormat DocstringFormat.PythonTripleQuote The docstring format (Python, JSDoc, Rustdoc, etc.).
Span Span Source span covering the docstring.
AssociatedItem *string nil Name of the item this docstring documents.
ParsedSections \[\]DocSection nil Parsed sections of the docstring (Args, Returns, Raises, etc.).

DownloadManager

Manages downloading and caching of pre-built parser shared libraries.

Methods
New()

Create a new download manager for the given version.

Signature:

func (o *DownloadManager) New(version string) (DownloadManager, error)

Example:

result, err := DownloadManager.New("value")
if err != nil {
    return err
}

Parameters:

Name Type Required Description
Version string Yes The version

Returns: DownloadManager

Errors: Returns error.

InstalledLanguages()

List languages that are already downloaded and cached.

Signature:

func (o *DownloadManager) InstalledLanguages() []string

Example:

result := instance.InstalledLanguages()

Returns: []string

DownloadAllBestEffort()

Download the platform bundle and extract every library file it contains.

Unlike Self.ensure_languages, this does not check the manifest language list against archive contents — it simply extracts all .so/.dylib/.dll files from the bundle. Languages in the manifest that are missing from the archive are silently ignored rather than returning an error.

Returns the number of library files extracted (including those already cached).

Signature:

func (o *DownloadManager) DownloadAllBestEffort() (int, error)

Example:

result, err := instance.DownloadAllBestEffort()
if err != nil {
    return err
}

Returns: int

Errors: Returns error.

CleanCache()

Remove all cached parser libraries.

Acquires the cross-process lock so clean_cache cannot race a concurrent downloader (avoids Windows sharing-violation errors against an in-flight bundle write). The .download.lock file itself is not removed — it is permanent infrastructure; deleting it could allow a concurrent process that already opened the file to continue holding a stale lock handle while a new process opens a fresh inode, breaking the mutual-exclusion guarantee.

Signature:

func (o *DownloadManager) CleanCache() error

Example:

if err := instance.CleanCache(); err != nil {
    return err
}

Returns: No return value.

Errors: Returns error.


ExportInfo

An export statement extracted from source code.

Field Type Default Description
Name string The exported name.
Kind ExportKind ExportKind.Named The kind of export (named, default, or re-export).
Span Span Source span covering the export statement.

FileMetrics

Aggregate metrics for a source file.

Field Type Default Description
TotalLines int Total number of lines (including blank and comment lines).
CodeLines int Number of lines containing non-blank, non-comment source code.
CommentLines int Number of lines that are entirely comments.
BlankLines int Number of blank (whitespace-only) lines.
TotalBytes int Total byte length of the source file.
NodeCount int Total number of nodes in the syntax tree.
ErrorCount int Number of error nodes in the syntax tree (parse errors).
MaxDepth int Maximum nesting depth reached in the syntax tree.

ImportInfo

An import statement extracted from source code.

Field Type Default Description
Source string The module or path being imported from.
Items \[\]string nil Specific names imported from the source module.
Alias *string nil Alias assigned to the import (e.g., import numpy as np).
IsWildcard bool Whether this is a wildcard import (e.g., import * or use foo.*).
Span Span Source span covering the import statement.

Language


LanguageRegistry

Thread-safe registry of tree-sitter language parsers.

Manages both statically compiled and dynamically loaded language grammars. Use LanguageRegistry.new() for the default registry, or access the global instance via the module-level convenience functions (get_language, available_languages, etc.).

Methods
New()

Create a new registry populated with all statically compiled languages.

When the dynamic-loading feature is enabled, the registry also knows about dynamically loadable grammars and will load them on demand.

Signature:

func (o *LanguageRegistry) New() LanguageRegistry

Example:

result := LanguageRegistry.New()

Returns: LanguageRegistry

GetLanguage()

Get a tree-sitter Language by name.

Resolves aliases (e.g., "shell" -> "bash", "makefile" -> "make"), then looks up the language in the static table. When the dynamic-loading feature is enabled, falls back to loading a shared library on demand.

Errors:

Returns Error.LanguageNotFound if the name (after alias resolution) does not match any known grammar.

Signature:

func (o *LanguageRegistry) GetLanguage(name string) (Language, error)

Example:

result, err := instance.GetLanguage("value")
if err != nil {
    return err
}

Parameters:

Name Type Required Description
Name string Yes The name

Returns: Language

Errors: Returns error.

AvailableLanguages()

List all available language names, sorted and deduplicated.

Includes statically compiled languages, dynamically loadable languages (if the dynamic-loading feature is enabled), and all configured aliases.

Signature:

func (o *LanguageRegistry) AvailableLanguages() []string

Example:

result := instance.AvailableLanguages()

Returns: []string

HasParser()

Check whether a parser is statically compiled into this build.

Returns true only when the grammar was compiled in at build time (i.e. it appears in the STATIC_LANGUAGES table). This is independent of the extension-to-language mapping: detect_language_from_extension consults the static ext table for all 306 grammars regardless of which parsers are compiled in.

Use this when you need to distinguish "we know the language name" from "we can actually parse files in that language right now".

use tree_sitter_language_pack::{detect_language_from_extension, LanguageRegistry};

let registry = LanguageRegistry::new();
// Extension detection uses the static table — independent of compiled parsers.
let lang = detect_language_from_extension("feature"); // always returns Some("gherkin")
// Parser availability depends on which grammars were compiled in.
let can_parse = lang.map(|name| registry.has_parser(name)).unwrap_or(false);

Signature:

func (o *LanguageRegistry) HasParser(name string) bool

Example:

result := instance.HasParser("value")

Parameters:

Name Type Required Description
Name string Yes The name

Returns: bool

HasLanguage()

Check whether a language is available by name or alias.

Returns true if the language can be loaded, either from the static table or from a dynamic library on disk.

Signature:

func (o *LanguageRegistry) HasLanguage(name string) bool

Example:

result := instance.HasLanguage("value")

Parameters:

Name Type Required Description
Name string Yes The name

Returns: bool

LanguageCount()

Return the total number of available languages (including aliases).

Signature:

func (o *LanguageRegistry) LanguageCount() int

Example:

result := instance.LanguageCount()

Returns: int

Process()

Parse source code and extract file intelligence based on config in a single pass.

Signature:

func (o *LanguageRegistry) Process(source string, config ProcessConfig) (ProcessResult, error)

Example:

result, err := instance.Process("value", ProcessConfig{})
if err != nil {
    return err
}

Parameters:

Name Type Required Description
Source string Yes The source
Config ProcessConfig Yes The configuration options

Returns: ProcessResult

Errors: Returns error.

Default()

Signature:

func (o *LanguageRegistry) Default() LanguageRegistry

Example:

result := LanguageRegistry.Default()

Returns: LanguageRegistry


Node

A single syntax node within a Tree.

Nodes hold a strong reference to their parent tree so they remain valid regardless of how the tree is moved or stored at the FFI boundary.

Methods
Clone()

Signature:

func (o *Node) Clone() Node

Example:

result := instance.Clone()

Returns: Node

Kind()

Return the node's kind name (e.g. "function_definition").

Signature:

func (o *Node) Kind() string

Example:

result := instance.Kind()

Returns: string

KindId()

Return the node's numeric kind ID.

Tree-sitter assigns a stable u16 ID to every node kind in a grammar (e.g. "function_definition" → 42). Comparing kind_id() is cheaper than comparing the string kind() in tight AST loops.

Signature:

func (o *Node) KindId() uint16

Example:

result := instance.KindId()

Returns: uint16

StartByte()

Return the inclusive start byte offset of this node.

Signature:

func (o *Node) StartByte() int

Example:

result := instance.StartByte()

Returns: int

EndByte()

Return the exclusive end byte offset of this node.

Signature:

func (o *Node) EndByte() int

Example:

result := instance.EndByte()

Returns: int

ByteRange()

Return the node's byte range as a ByteRange.

Callers should slice their own source bytes — this is a zero-copy text accessor.

Signature:

func (o *Node) ByteRange() ByteRange

Example:

result := instance.ByteRange()

Returns: ByteRange

StartPosition()

Return the start Point (row, column).

Signature:

func (o *Node) StartPosition() Point

Example:

result := instance.StartPosition()

Returns: Point

EndPosition()

Return the end Point (row, column).

Signature:

func (o *Node) EndPosition() Point

Example:

result := instance.EndPosition()

Returns: Point

IsNamed()

True when this node is named (not punctuation/whitespace).

Signature:

func (o *Node) IsNamed() bool

Example:

result := instance.IsNamed()

Returns: bool

IsError()

True when this is an error node.

Signature:

func (o *Node) IsError() bool

Example:

result := instance.IsError()

Returns: bool

IsMissing()

True when this is a missing-token node.

Signature:

func (o *Node) IsMissing() bool

Example:

result := instance.IsMissing()

Returns: bool

IsExtra()

True when this is an "extra" node (e.g. a comment).

Signature:

func (o *Node) IsExtra() bool

Example:

result := instance.IsExtra()

Returns: bool

HasError()

True when this node or any descendant is an error.

Signature:

func (o *Node) HasError() bool

Example:

result := instance.HasError()

Returns: bool

Parent()

Return this node's parent, if any.

Signature:

func (o *Node) Parent() *Node

Example:

result := instance.Parent()

Returns: *Node

Child()

Return the i-th child of this node, if any.

Signature:

func (o *Node) Child(index uint32) *Node

Example:

result := instance.Child(42)

Parameters:

Name Type Required Description
Index uint32 Yes The index

Returns: *Node

ChildCount()

Total number of children (including unnamed).

Signature:

func (o *Node) ChildCount() int

Example:

result := instance.ChildCount()

Returns: int

NamedChild()

Return the i-th named child of this node, if any.

Signature:

func (o *Node) NamedChild(index uint32) *Node

Example:

result := instance.NamedChild(42)

Parameters:

Name Type Required Description
Index uint32 Yes The index

Returns: *Node

NamedChildCount()

Number of named children of this node.

Signature:

func (o *Node) NamedChildCount() int

Example:

result := instance.NamedChildCount()

Returns: int

ChildByFieldName()

Look up a child by its grammar-defined field name.

Signature:

func (o *Node) ChildByFieldName(name string) *Node

Example:

result := instance.ChildByFieldName("value")

Parameters:

Name Type Required Description
Name string Yes The name

Returns: *Node

ToSexp()

Return the S-expression form of this node's subtree.

Signature:

func (o *Node) ToSexp() string

Example:

result := instance.ToSexp()

Returns: string

Walk()

Return a TreeCursor positioned at this node.

Signature:

func (o *Node) Walk() TreeCursor

Example:

result := instance.Walk()

Returns: TreeCursor


PackConfig

Configuration for the tree-sitter language pack.

Controls cache directory and which languages to pre-download. Can be loaded from a TOML file, constructed programmatically, or passed as a dict/object from language bindings.

Field Type Default Description
CacheDir *string nil Override default cache directory. Default: ~/.cache/tree-sitter-language-pack/v{version}/libs/
Languages *\[\]string nil Languages to pre-download on init. Each entry is a language name (e.g. "python", "rust").
Groups *\[\]string nil Language groups to pre-download (e.g. "web", "systems", "scripting").

Parser

A tree-sitter parser configured for one language at a time.

Methods
New()

Construct a new parser with no language set.

Call Parser.set_language before parsing.

Signature:

func (o *Parser) New() Parser

Example:

result := Parser.New()

Returns: Parser

SetLanguage()

Configure the parser to use the language identified by name (e.g. "python").

Resolves the language through the global registry — auto-downloading if necessary, when the download feature is enabled.

Errors:

Returns Error.LanguageNotFound if the language is not recognized, or Error.ParserSetup if the language ABI is incompatible.

Signature:

func (o *Parser) SetLanguage(name string) error

Example:

if err := instance.SetLanguage("value"); err != nil {
    return err
}

Parameters:

Name Type Required Description
Name string Yes The name

Returns: No return value.

Errors: Returns error.

Parse()

Parse a UTF-8 source string. Returns nil if parsing was cancelled or no language is set.

Signature:

func (o *Parser) Parse(source string) *Tree

Example:

result := instance.Parse("value")

Parameters:

Name Type Required Description
Source string Yes The source

Returns: *Tree

ParseBytes()

Parse a raw byte slice. Returns nil if parsing was cancelled or no language is set.

Signature:

func (o *Parser) ParseBytes(source []byte) *Tree

Example:

result := instance.ParseBytes([]byte("data"))

Parameters:

Name Type Required Description
Source \[\]byte Yes The source

Returns: *Tree

Reset()

Reset internal state. The next call to parse will not be incremental.

Signature:

func (o *Parser) Reset()

Example:

instance.Reset()

Returns: No return value.

Default()

Signature:

func (o *Parser) Default() Parser

Example:

result := Parser.Default()

Returns: Parser


Point

A source position — row + column, zero-indexed.

Field Type Default Description
Row int Zero-indexed row number.
Column int Zero-indexed column number, in UTF-16 code units.

ProcessConfig

Configuration for the process() function.

Controls which analysis features are enabled and whether chunking is performed.

Field Type Default Description
Language string Language name (required).
Structure bool true Extract structural items (functions, classes, etc.). Default: true.
Imports bool true Extract import statements. Default: true.
Exports bool true Extract export statements. Default: true.
Comments bool false Extract comments. Default: false.
Docstrings bool false Extract docstrings. Default: false.
Symbols bool false Extract symbol definitions. Default: false.
Diagnostics bool false Include parse diagnostics. Default: false.
ChunkMaxSize *int nil Maximum chunk size in bytes. nil disables chunking.
DataExtraction bool false Extract hierarchical key/value data tree from data-format files. Default: false. When true, ProcessResult.data is populated with a DataNode tree for supported languages: JSON, YAML, TOML, .properties, HCL/HOCON, INI, editorconfig, KDL, CUE, CSV, PSV, PO, nginx config, Caddy config, XML, and DTD. For languages outside this set the field is left as nil.
Methods
Default()

Signature:

func (o *ProcessConfig) Default() ProcessConfig

Example:

result := ProcessConfig.Default()

Returns: ProcessConfig

WithChunking()

Enable chunking with the given maximum chunk size in bytes.

Signature:

func (o *ProcessConfig) WithChunking(maxSize int) ProcessConfig

Example:

result := instance.WithChunking(42)

Parameters:

Name Type Required Description
MaxSize int Yes The max size

Returns: ProcessConfig

All()

Enable all analysis features.

Signature:

func (o *ProcessConfig) All() ProcessConfig

Example:

result := instance.All()

Returns: ProcessConfig

Minimal()

Disable all analysis features (only metrics computed).

Signature:

func (o *ProcessConfig) Minimal() ProcessConfig

Example:

result := instance.Minimal()

Returns: ProcessConfig

WithDataExtraction()

Enable or disable hierarchical data extraction for data-format files.

When true, ProcessResult.data is populated with a key/value tree for supported data-format languages.

Signature:

func (o *ProcessConfig) WithDataExtraction(enabled bool) ProcessConfig

Example:

result := instance.WithDataExtraction(true)

Parameters:

Name Type Required Description
Enabled bool Yes The enabled

Returns: ProcessConfig


ProcessResult

Complete analysis result from processing a source file.

Contains metrics, structural analysis, imports/exports, comments, docstrings, symbols, diagnostics, and optionally chunked code segments. Fields are populated based on the ProcessConfig flags.

Field Type Default Description
Language string The language name used to parse the source file.
Metrics FileMetrics File-level metrics (line counts, byte size, error count).
Structure \[\]StructureItem nil Top-level structural items (functions, classes, etc.).
Imports \[\]ImportInfo nil Import statements extracted from the source.
Exports \[\]ExportInfo nil Export statements extracted from the source.
Comments \[\]CommentInfo nil Comments extracted from the source.
Docstrings \[\]DocstringInfo nil Docstrings extracted from the source.
Symbols \[\]SymbolInfo nil Symbol definitions (variables, types, functions) extracted from the source.
Diagnostics \[\]Diagnostic nil Parse diagnostics (syntax errors, missing nodes) from tree-sitter.
Chunks \[\]CodeChunk nil Syntax-aware code chunks produced when chunking is enabled.
Data *DataNode nil Hierarchical data tree extracted when config.data_extraction is true. Populated for supported data-format languages (JSON, YAML, TOML, properties, HCL, INI, XML, CSV, and more). nil when data_extraction is false (the default) or when the language is not a recognised data format. See DataNode for the shape of the returned tree.

Span

Byte and line/column range in source code.

Represents both byte offsets (for slicing) and human-readable line/column positions (for display and diagnostics).

Field Type Default Description
StartByte int Inclusive start byte offset in the source.
EndByte int Exclusive end byte offset in the source.
StartLine int Zero-indexed line number of the span's start.
StartColumn int Zero-indexed column number of the span's start.
EndLine int Zero-indexed line number of the span's end.
EndColumn int Zero-indexed column number of the span's end.

StructureItem

A structural item (function, class, struct, etc.) in source code.

Field Type Default Description
Kind StructureKind StructureKind.Function The kind of structural item.
Name *string nil The declared name of the item, if present.
Visibility *string nil Visibility modifier (e.g., "pub", "public", "private").
Span Span Source span covering the entire item declaration.
Children \[\]StructureItem nil Nested structural items (e.g., methods within a class).
Decorators \[\]string nil Decorator or attribute names applied to the item.
DocComment *string nil Documentation comment attached to the item, if any.
Signature *string nil Full signature text of the item (e.g., function parameters and return type).
BodySpan *Span nil Source span covering only the body of the item, if distinct from the declaration.

SymbolInfo

A symbol (variable, function, type, etc.) extracted from source code.

Field Type Default Description
Name string The name of the symbol.
Kind SymbolKind SymbolKind.Variable The kind of symbol (variable, function, class, etc.).
Span Span Source span covering the symbol definition.
TypeAnnotation *string nil Explicit type annotation, if present in the source.
Doc *string nil Documentation comment associated with this symbol.

Tree

A parsed syntax tree. Cheap to clone (refcount bump).

Methods
RootNode()

Return the root Node of this tree.

Signature:

func (o *Tree) RootNode() Node

Example:

result := instance.RootNode()

Returns: Node

Walk()

Return a TreeCursor positioned at the root.

Signature:

func (o *Tree) Walk() TreeCursor

Example:

result := instance.Walk()

Returns: TreeCursor


TreeCursor

A cursor for traversing a Tree.

Methods
Node()

Return the Node at the cursor's current position.

Signature:

func (o *TreeCursor) Node() Node

Example:

result := instance.Node()

Returns: Node

GotoFirstChild()

Move the cursor to the first child of the current node. Returns true if a child existed.

Signature:

func (o *TreeCursor) GotoFirstChild() bool

Example:

result := instance.GotoFirstChild()

Returns: bool

GotoParent()

Move the cursor to the parent of the current node. Returns true if a parent existed.

Signature:

func (o *TreeCursor) GotoParent() bool

Example:

result := instance.GotoParent()

Returns: bool

GotoNextSibling()

Move the cursor to the next sibling of the current node. Returns true if a sibling existed.

Signature:

func (o *TreeCursor) GotoNextSibling() bool

Example:

result := instance.GotoNextSibling()

Returns: bool

FieldName()

Return the field name for the current node, if any.

Signature:

func (o *TreeCursor) FieldName() *string

Example:

result := instance.FieldName()

Returns: *string


Enums

DataNodeKind

The kind of a data node extracted from a data-format file.

Classifies each node in the hierarchical DataNode tree returned when data_extraction is enabled on ProcessConfig.

Wire format (public JSON contract)

Unit variants serialize as a bare string ("KeyValue"). DO NOT add #[serde(tag = "...")] or rename variants — every language binding has a hand-written deserializer matching this exact shape, and any change breaks all bindings' process() tests simultaneously. Covered by tests/wire_format.rs.

Value Description
KeyValue A key/value pair or mapping (json/toml/properties/yaml/hcl/cue/kdl pair, or a wrapper "object"/"mapping" container).
Element An XML element with a tag name in key and attributes in attributes.
Sequence A positional sequence item (JSON array element, YAML block sequence item, CSV/PSV row or cell).

StructureKind

The kind of structural item found in source code.

Categorizes top-level and nested declarations such as functions, classes, structs, enums, traits, and more. Use Other for language-specific constructs that do not fit a standard category.

Wire format (public JSON contract)

Unit variants serialize as a bare string ("Function"); the Other variant serializes as a single-keyed object ({"Other": "macro"}). DO NOT add #[serde(tag = "...")] or rename variants — every language binding has a hand-written deserializer matching this exact shape, and any change breaks all bindings' process() tests simultaneously. Covered by tests/wire_format.rs.

Value Description
Function A free-standing or associated function.
Method A method defined inside a class, struct, trait, or impl block.
Class A class definition.
Struct A struct definition.
Interface An interface or protocol definition.
Enum An enum definition.
Module A module or package declaration.
Trait A trait definition.
Impl An impl block (Rust) or similar implementation block.
Namespace A namespace declaration.
Other A language-specific construct that does not fit any standard category. — Fields: 0: string

CommentKind

The kind of a comment found in source code.

Distinguishes between single-line comments, block (multi-line) comments, and documentation comments.

Value Description
Line A single-line comment (e.g., // ... or # ...).
Block A block or multi-line comment using slash-star delimiters.
Doc A documentation comment such as /// ... or slash-double-star block.

DocstringFormat

The format of a docstring extracted from source code.

Identifies the docstring convention used, which varies by language (e.g., Python triple-quoted strings, JSDoc, Rustdoc /// comments).

Wire format (public JSON contract)

Unit variants serialize as a bare string ("JSDoc"); the Other variant serializes as a single-keyed object ({"Other": "rst"}). DO NOT add #[serde(tag = "...")]. Covered by tests/wire_format.rs.

Value Description
PythonTripleQuote Python triple-quoted string docstring ("""...""").
JsDoc JavaScript/TypeScript JSDoc block comment (opens with two stars, closes with star-slash).
Rustdoc Rust /// or //! doc comment.
GoDoc Go doc comment (a comment block immediately preceding a declaration).
JavaDoc Java Javadoc block comment (opens with two stars, closes with star-slash).
Other A language-specific docstring format not covered by the standard variants. — Fields: 0: string

ExportKind

The kind of an export statement found in source code.

Covers named exports, default exports, and re-exports from other modules.

Value Description
Named A named export (e.g., export { foo }).
Default A default export (e.g., export default foo).
ReExport A re-export from another module (e.g., export { foo } from 'bar').

SymbolKind

The kind of a symbol definition found in source code.

Categorizes symbol definitions such as variables, constants, functions, classes, types, interfaces, enums, and modules.

Wire format (public JSON contract)

Unit variants serialize as a bare string ("Function"); the Other variant serializes as a single-keyed object ({"Other": "macro"}). DO NOT add #[serde(tag = "...")]. Covered by tests/wire_format.rs.

Value Description
Variable A variable binding.
Constant A constant (immutable binding).
Function A function definition.
Class A class definition.
Type A type alias or typedef.
Interface An interface definition.
Enum An enum definition.
Module A module declaration.
Other A symbol kind not covered by the standard variants. — Fields: 0: string

DiagnosticSeverity

Severity level of a diagnostic produced during parsing.

Used to classify parse errors, warnings, and informational messages found in the syntax tree.

Value Description
Error A parse error (e.g., an ERROR or MISSING node in the tree).
Warning A warning-level diagnostic.
Info An informational diagnostic.

Errors

Error

Errors that can occur when using the tree-sitter language pack.

Covers language lookup failures, parse errors, query errors, and I/O issues. Feature-gated variants are included when config, download, or related features are enabled.

Variant Description
LanguageNotFound The requested language name (or alias) was not found in the registry.
DynamicLoad A dynamic shared library could not be loaded at runtime.
NullLanguagePointer The tree-sitter language function returned a null pointer for the given language name.
ParserSetup The language could not be applied to the parser (e.g., ABI version mismatch).
LockPoisoned An internal RwLock or Mutex was poisoned by a previous panic.
Config A configuration file or value was invalid or could not be applied.
ParseFailed The tree-sitter parser returned no tree for the given source input.
QueryError A tree-sitter query could not be compiled or executed.
InvalidRange A byte range was invalid (e.g., end before start, or out of bounds).
Download A parser download from GitHub releases failed.
ChecksumMismatch The downloaded file's SHA-256 digest did not match the manifest's expected value.
CacheLock The cross-process download cache lock file could not be acquired or created.

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