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Strict Reflect.apply Reflect.construct and Function.prototype.apply/call/bind #33889
Description
Activity
I'd expect
Function.prototype.apply(null, getString);to error, like(Function.prototype as CallableFunction).apply(null, getString);:error TS2684: The 'this' context of type 'CallableFunction' is not assignable to method's 'this' of type '(this: any, ...args: any[]) => unknown'. Type 'CallableFunction' provides no match for the signature '(this: any, ...args: any[]): unknown'.--stringBindCallApplyshould apply theCallableFunctioninterface to theFunctionglobal as well as to function instances?The original use case code has an error and has been fixed.
Since
Reflect.applyis easier to use thanFunction.prototype.applyandReflect.constructprovides feature thatFunction.prototypedoes not have, maybe we don't need to applyCallableFunctioninterface toFunction, we just need to improveReflect.applyandReflect.construct.Just checking whether the spread operator available to you?
const args = []; new ClassA(...args); // ClassA
This is not an issue about how to dynamically create an object instance.
Would you consider adding more information about your use case?
This issue is equivalent to say: add type guard for
Reflect.applyunder--strictBindCallApply.Example:
function foo(name: string) { console.log(name) } foo.apply(null, [42]); // typescript will report type error, great! Function.prototype.apply.call(foo, null, [42]); // no error 😢 Reflect.apply(foo, null, [42]); // no error 😢
Search Terms
Reflect.apply
Reflect.construct
Function.prototype.apply
Function.prototype.call
Function.prototype.bind
Suggestion
These functions should not return
any.Related:
#212
#27028
Use Cases
Examples
Reflect:
Checklist
My suggestion meets these guidelines:
👆 Add a new compiler option