WebAssembly types

This section documents the different WebAssembly types.

Reference types

externref

References a JavaScript value, enabling it to be given to a Wasm module without the need for copying or serializing.

funcref

References a function defined in Wasm, enabling higher-order functions to be used across the Wasm and JavaScript language boundaries.

Value types

v128

A vector type representing a 128-bit vector of packed integer or floating-point data. A v128 value can be interpreted in several different ways by SIMD instructions.