WEPL

The WebAssembly Component repl.

Building from Source

You can build wepl from source by running cargo build --release (or cargo build to build in debug mode).

Installing `wepl`

You can install wepl from crates.io by running cargo install wepl --locked.

You can also install wepl on your local system by running cargo install --path . --locked.

Example

$ wepl mycomponent.wasm
> .exports
uppercase: func(input: string) -> string
> uppercase
uppercase: func(input: string) -> string
> s = "hello"
s: string
> uppercase(s)
"HELLO"

Built-in Functions

Built-in functions can be called by using the . prefix.

Supported functions include:

.imports: print a list of all the component's imports
.exports: print a list of all the component's exports
.link $function $wasm: satisfy the imported function $func with an export from the wasm component $wasm
.compose $adapter: satisfy imports with the supplied adapter module (e.g., to compose with WASI-Virt adapter)
.type $type: inspect a type's $type definition in scope
.help: print help information (? is alias for this built-in)

Features

Exported function evaluation
Listing imports and exports
Variable assignment
Type checking
Satisfying imports with other WebAssembly Components
Basic component composition

Compatibility

wepl is currently tied to the wasmtime 17 release. Components that work with that release should work in wepl.

rylev/wepl