Crate intern_lang 

intern_lang

Fast string and symbol interning — identifier comparisons become integer comparisons.

intern-lang maps each distinct string to a small, copyable Symbol, stores the bytes once in a contiguous backing store, and hands back integer handles. A compiler front-end interns every identifier once, then compares and passes symbols instead of strings: a name comparison becomes an integer comparison, and a name in an AST node costs four bytes instead of an owned String. It is the deduplication layer beneath a lexer and a symbol table, and it owns interning and nothing else — no lexing, no scoping, no I/O.

At a glance

• Interner — the single-threaded interner. intern deduplicates and returns a stable Symbol; resolve borrows the bytes back out of the store.
• Symbol — a four-byte Copy handle whose equality, ordering, and hashing are integer operations.
• ConcurrentInterner — a thread-safe interner many threads can intern into at once, sharing one symbol space (requires the std feature).
• Lookup — the read-side trait both interners implement, so generic code can accept either.

Example

use intern_lang::Interner;

let mut interner = Interner::new();

// Interning the same string twice yields the same symbol...
let a = interner.intern("while");
let b = interner.intern("while");
assert_eq!(a, b);

// ...and distinct strings yield distinct symbols.
let c = interner.intern("for");
assert_ne!(a, c);

// Comparing names is now an integer compare; resolving borrows the bytes.
assert_eq!(interner.resolve(a), Some("while"));
assert_eq!(interner.resolve(c), Some("for"));

no_std

The crate is no_std-compatible: it relies only on alloc, never on the standard library. The default std feature is additive. Disable default features to build for a no_std target.

Structs

ConcurrentInternerstd

A thread-safe string interner that many threads can intern into at once.

Interner

A single-threaded string interner.

Symbol

A small, copyable handle to a string held by an Interner.

Enums

InternError

An error returned when a string cannot be interned.

Traits

Lookup

The read-side contract every interner in the crate implements.