Meriyah does not properly follow ECMA standards on function declaration and calling.

When experimenting with Meriyah, I discovered the parser properly registers the following invalid function declarations and calls:

function 10() {
   return 10;
}

10();

function "string"() {
   return "string"();
}

"string"();

Meriyah also struggles when calling functions. It will assume that the name of the function being called is an identifier, and not a literal.

[3cp]

NVM, my mistake, []() and ({}()) is runtime error too 😃

[3cp]

Other parsers like acorn and TS do not reject them.