Instantiate JS objects more easily (pm.new?)

[wiwichips]

Describe your feature request here.

The pattern I've been using to instantiate new JS objects from classes is to wrap the call to "new" in a function:

module = pm.eval("(bufferSource) => new WebAssembly.Module(bufferSource)")(file_buffer)

This gets uglier when you need to pass more things to a constructor:

wasm_instance = pm.eval("(module, importObject) => new WebAssembly.Instance(module, importObject)")(module, import_object)

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I think it would be nicer to have some better way of doing "new" since its such a commonly used operator.

WebAssembly = pm.eval("WebAssembly")
module = pm.new(WebAssembly.Module)(file_buffer)
wasm_instance = pm.new(WebAssembly.Instance)(module, import_object)

I'm not sure if this is the best approach, but just an idea

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NOTE: some JS constructors don't require the use of the 'new' keyword... but others like WebAssembly.Module will and will report the following error if not used with new Uncaught TypeError: WebAssembly.Module(): WebAssembly.Module must be invoked with 'new'

Code example

API idea:
new method: pm.new
parameters: a function which is a constructor
return: a function which calls the constructor

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Usage: pm.new(SomeConstructor)(parameters...)

pm.new(Function)(

[wiwichips]

I guess alternatively, better handling for JS Classes... treat JS classes like Python classes... 🤔 - I feel like that would be more complicated and confusing for users

[wesgarland]

I like the initial idea. new in JS is actually an operator which is semantically more like type() in python than construction. (JS typeof is also an operator)

Implementing this in PythonMonkey would be very straightforward. We should allow either string or function arguments. String arguments would be evaluated in the global scope to yield functions.

instance = pm.new("Constructor", arg1, arg2, arg3)
instance = pm.new(pm.eval("Constructor"), arg1, arg2, arg3)

would then be the same

and with this semantic, we could also

instance = pm.new(pm.require("myModule").Constructor, arg1, arg2, arg))

[wesgarland]

See branch feature/pm-new-bug-144