Add in WAST

Input

(module
  (func $add (param i32) (param i32) (result i32)
    (get_local 0)
    (get_local 1)
    (i32.add)
  )
  (export "add" (func $add))
)

Client

var code = document.getElementById("input").innerText;
var module = webassemblyjs.instantiateFromSource(code);

var res = module.exports.add(1, 1);
document.getElementById("res").innerHTML = res;

Result

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