[][src]Macro sp_core::wasm_export_functions

macro_rules! wasm_export_functions {
    (
		$(
			fn $name:ident (
				$( $arg_name:ident: $arg_ty:ty ),* $(,)?
			) $( -> $ret_ty:ty )? { $( $fn_impl:tt )* }
		)*
	) => { ... };
    (@IMPL
		fn $name:ident (
				$( $arg_name:ident: $arg_ty:ty ),*
		) { $( $fn_impl:tt )* }
	) => { ... };
    (@IMPL
		fn $name:ident (
				$( $arg_name:ident: $arg_ty:ty ),*
		) $( -> $ret_ty:ty )? { $( $fn_impl:tt )* }
	) => { ... };
}

Macro for exporting functions from wasm in with the expected signature for using it with the wasm executor. This is useful for tests where you need to call a function in wasm.

The input parameters are expected to be SCALE encoded and will be automatically decoded for you. The output value is also SCALE encoded when returned back to the host.

The functions are feature-gated with #[cfg(not(feature = "std"))], so they are only available from within wasm.

Example

wasm_export_functions! {
    fn test_in_wasm(value: bool, another_value: Vec<u8>) -> bool {
        value && another_value.is_empty()
    }

    fn without_return_value() {
        // do something
    }
}