function_restriction.md

Feature - Function Restriction

In a JavaScript module, it is recommended to export function only so that the module is tamper proof. The function restriction ensure the following.

• There are no module wide statements other than function declarations.
• There are some functions that must be declared.
• To a particular function, the argument count can be also validated.

JavetSanitizerModuleFunctionChecker is the one that enforces this check.

Valid Sample

import { x } from 'x.mjs';

function main() {
  // Do something.
}

Invalid Samples

const a = 1; // Variable declaration is invalid.
class A {} // Class declaration is invalid.
JSON.stringify(undefined); // Regular statement is invalid.

List

The default must-have function list is as follows:

main

Please refer to the tutorial for more details.