Struct wasmer_ruby::Wasmer::Function

pub struct Function;

Represents a WebAssembly function instance.

A function instance is the runtime representation of a function. It effectively is a closure of the original function (defined in either the host or the WebAssembly module) over the runtime Instance of its originating Module.

The module instance is used to resolve references to other definitions during executing of the function.

Specification: https://webassembly.github.io/spec/core/exec/runtime.html#function-instances

Note that the function can be invoked/called by the host only when it is an exported function (see Exports to see an example).

Example

To build a Function, we need its type. Function understands Symbol, Proc, and Lambda.

First, a function through a symbol:

def foo(x)
  x + 1
end

function = Wasmer::Function.new(
  Wasmer::Store.new,
  # A symbol.
  method(:foo),
  Wasmer::FunctionType.new([Wasmer::Type::I32], [])
)

Second, a function through a proc as a lambda:

function = Wasmer::Function.new(
  Wasmer::Store.new,
  # A lambda.
  -> (x) { x + 1 },
  Wasmer::FunctionType.new([Wasmer::Type::I32], [])
)

Third, a function through a proc:

function = Wasmer::Function.new(
  Wasmer::Store.new,
  # A proc.
  Proc.new { |x| x + 1 },
  Wasmer::FunctionType.new([Wasmer::Type::I32], [])
)

Implementations

impl Function

pub fn new(store: Store, function: Any, function_type: FunctionType) -> Self

Creates a new Function. The function can be of kind Symbol, Proc or Lambda.

pub fn call(x0: Any, x1: Any, x2: Any, etc: Any) -> Any

Calls the function with arguments. It returns zero or more results.

pub fn type(&self) -> FunctionType

Returns the function type.