Struct FunctionIndex 

pub struct FunctionIndex {
    pub stats: IndexStats,
    /* private fields */
}

Arena-based function index that stores each function once and uses indices for multiple lookup strategies.

Provides O(1) lookup by name, qualified name, file+name, or class+method. Handles ambiguity when multiple functions share the same name.

Memory Efficiency

Each FunctionDef is stored exactly once in the functions arena. All lookup maps use usize indices into this arena, reducing memory from ~7x duplication (with Arc clones) to 1x + indices.

For a project with 10,000 functions:

• Old: 10,000 FunctionDefs + ~50,000 Arc clones
• New: 10,000 FunctionDefs + ~50,000 usize indices (8 bytes each)

Fields

stats: IndexStats

Statistics for debugging

Implementations

impl FunctionIndex

pub fn build(files: &[PathBuf]) -> Result<Self>

Build index from a list of source files using parallel extraction.

Uses rayon for parallel file processing, then merges results.

Arguments

• files - List of source file paths to index

Returns

• Result<Self> - Built index or error

pub fn build_with_root(files: &[PathBuf], root: Option<&Path>) -> Result<Self>

Build index with an explicit project root for relative path calculation.

Arguments

• files - List of source file paths to index
• root - Optional project root for computing relative paths

Returns

• Result<Self> - Built index or error

pub fn lookup(&self, name: &str) -> Vec<&FunctionRef>

Look up all functions with a given simple name.

Returns all functions matching the name, which may be in different files or classes. Use lookup_qualified or lookup_in_file for more precise lookups.

Arguments

• name - Simple function name (without module/class prefix)

Returns

• Vec<&FunctionRef> - All matching function references

pub fn lookup_qualified(&self, qname: &str) -> Option<&FunctionRef>

Look up a function by its fully qualified name.

Arguments

• qname - Fully qualified name (e.g., “module.Class.method”)

Returns

• Option<&FunctionRef> - Function reference if found

pub fn lookup_in_file(&self, file: &str, name: &str) -> Option<&FunctionRef>

Look up a function in a specific file by name.

Useful for resolving calls within the same file or to known modules.

Arguments

• file - File path (relative or absolute)
• name - Function name

Returns

• Option<&FunctionRef> - Function reference if found

pub fn lookup_method( &self, class_name: &str, method_name: &str, ) -> Vec<&FunctionRef>

Look up a method in a specific class.

Uses the by_class_method secondary index for O(1) average-case lookup. Returns all methods matching the class and method name (may exist in multiple files with the same class name).

Arguments

• class_name - Name of the class
• method_name - Name of the method

Returns

• Vec<&FunctionRef> - All matching method references

Performance

O(1) average case via HashMap lookup, O(k) where k is the number of methods with the same class/method name in different files.

pub fn lookup_simple( &self, simple_module: &str, func_name: &str, ) -> Vec<&FunctionRef>

Look up functions by simple module name and function name.

Enables lookups like “module.func” even when the full qualified name is “pkg.subpkg.module.func”. This matches Python’s indexing strategy where both full and simple module names are indexed.

Arguments

• simple_module - Module basename without extension (e.g., “utils”, “helper”)
• func_name - Function name

Returns

• Vec<&FunctionRef> - All matching function references

Performance

O(1) average case via HashMap lookup.

Example

// For a function defined in pkg/subpkg/utils.py:
index.lookup_simple("utils", "helper_func") // Finds it!

pub fn get_definition(&self, qname: &str) -> Option<&FunctionDef>

Get full metadata for a function by qualified name.

Arguments

• qname - Fully qualified name

Returns

• Option<&FunctionDef> - Full function metadata if found

pub fn all_functions(&self) -> impl Iterator<Item = &FunctionRef>

Get all functions in the index.

pub fn len(&self) -> usize

Get the number of indexed functions.

pub fn is_empty(&self) -> bool

Check if the index is empty.

pub fn files(&self) -> impl Iterator<Item = &String>

Get all file paths in the index.

pub fn contains(&self, name: &str) -> bool

Check if a function exists by simple name.

pub fn statistics(&self) -> &IndexStats

Get statistics about the index.

pub fn iter(&self) -> impl Iterator<Item = &FunctionDef>

Iterate over all function definitions.

Provides access to full FunctionDef metadata for all indexed functions.

Trait Implementations

impl Debug for FunctionIndex

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for FunctionIndex

fn default() -> FunctionIndex

Returns the “default value” for a type.