In a regular script a function can be invoked by string name as window["myFunc"]().
Is there an equivalent in a JS script of type="module" at the "top level", apart from declaring an object and assigning a method to it?
Thank you.
Add a comment
|
2 Answers
No - one of the main benefits of modules is to allow code that avoids that sort of global pollution. The top level of a module works similarly to an IIFE - the module can see everything that's global, but nothing can see what's declared inside the module, except that, also:
- Modules can import from other modules
- Modules can export to other modules
While you technically can do something like
window.foo = 'foo';
inside a module, writing scripts that use that route defeats the purpose of using a module system at all. Explicit dependencies make code more maintainable.
answered Sep 16, 2022 at 1:03
CertainPerformance
373k55 gold badges354 silver badges359 bronze badges
4 Comments
Gary
Within a module's scope or its inner global namespace (I don't know a better term for it) to what are function delcarations assigned?
CertainPerformance
To the environment that is the top level of the module - just like how standard variable definitions
const foo = 'bar'; are assigned to their environment (which is usually the enclosing block - or top level, if there is no enclosing block). If you're not doing anything weird and understand the hoisting implications, you can consider function fn() { ... to be equivalent to const fn = function() { for most purposes - it's just like the declaration of another variable.Gary
Thank you. I wasn't getting it, of course; but seem to understand now.
Johncl
Not sure I quite agree with that this is a benefit. Clearly you can define variables in a module directly without defining them inside another scope, but for some reason you cant access this "module" scope like you can global scope through "window" parent object. I wish there was at least a "module" object that you could access within the module itself. The extreme flexibility of Javascript is what I love about the language, but here they have somehow ignored that.