# Wasmer Interface Types
Wasmer is a standalone JIT WebAssembly runtime, aiming to be fully
compatible with WASI, Emscripten, Rust and Go. [Learn
more](https://github.com/wasmerio/wasmer).
This crate is an implementation of [the living WebAssembly Interface
Types standard](https://github.com/WebAssembly/interface-types).
## Encoders and decoders
The `wasmer-interface-types` crate comes with an encoder and a decoder
for the WAT format, and the binary format, for the WebAssembly
Interface Types. An encoder writes an AST into another format, like
WAT or binary. A decoder reads an AST from another format, like WAT or
binary.
## Instructions
Very basically, WebAssembly Interface Types defines a set of
instructions, used by adapters to transform the data between
WebAssembly core and the outside world ([learn
mode](https://github.com/WebAssembly/interface-types/blob/master/proposals/interface-types/Explainer.md)).
Here is the instructions that are implemented:
| Instruction | WAT encoder | Binary encoder | WAT decoder | Binary decoder | Interpreter |
|-|-|-|-|-|-|
| `arg.get` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `call-core` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `memory-to-string` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `string-to-memory` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `call-adapter` | ❌ | ❌ | ❌ | ❌ | ❌ |
| `defer-call-core` | ❌ | ❌ | ❌ | ❌ | ❌ |
| `i32-to-s8` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i32-to-s8x` | ✅ | ✅ | ✅ | ✅ | ❌ |
| `i32-to-u8` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i32-to-s16` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i32-to-s16x` | ✅ | ✅ | ✅ | ✅ | ❌ |
| `i32-to-u16` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i32-to-s32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i32-to-u32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i32-to-s64` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i32-to-u64` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i64-to-s8` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i64-to-s8x` | ✅ | ✅ | ✅ | ✅ | ❌ |
| `i64-to-u8` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i64-to-s16` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i64-to-s16x` | ✅ | ✅ | ✅ | ✅ | ❌ |
| `i64-to-u16` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i64-to-s32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i64-to-s32x` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i64-to-u32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i64-to-s64` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `i64-to-u64` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `s8-to-i32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `u8-to-i32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `s16-to-i32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `u16-to-i32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `s32-to-i32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `u32-to-i32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `s64-to-i32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `s64-to-i32x` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `u64-to-i32` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `u64-to-i32x` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `s8-to-i64` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `u8-to-i64` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `s16-to-i64` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `u16-to-i64` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `s32-to-i64` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `u32-to-i64` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `s64-to-i64` | ✅ | ✅ | ✅ | ✅ | ✅ |
| `u64-to-i64` | ✅ | ✅ | ✅ | ✅ | ✅ |