Scryer Prolog documentation

Module wasm

:- use_module(library(wasm)).

Predicates for the WebAssembly platform

This module contains predicates that are only available in the WASM (WebAssembly) version of Scryer Prolog.

js_eval(+JsCode, -Result).

Executes a JavaScript snippet JsCode using the platform eval function. Result takes the return value of that code. Strings, booleans, numbers, null and undefined are directly mapped to Prolog. Arrays, objects, bigints, symbols and functions are not mapped. Instead, a js_{type} atom will be returned.

Example (on a browser):


?- js_eval("prompt('What is your name?')", Name).
   % A prompt is showed, with a textbox.
   Name = "Whatever was written on the textbox".