Comment by stefano

Having implemented a threaded Forth with WASM, the most annoying problem is that WASM doesn't support jumps to arbitrary memory locations. You can either call functions (and you don't have access to the call stack), jump backward to a previously defined block entry point or jump forward to the end of a previously defined block. Threading then requires a double indirection in the core loop, and you have to use an explicit IP "register" in a global variable.