35. Function.prototype.call

Easy•

The Function.prototype.call() method invokes a function immediately with a specified this value and arguments passed individually.

Implement your own Function.prototype.call without using the native call, apply, or bind methods. To avoid overriding the built-in method, implement it as Function.prototype.myCall.

Example

function greet(greeting) {
  return `${greeting}, ${this.name}`;
}

const user = { name: "Alice" };

greet.myCall(user, "Hello"); // "Hello, Alice"

Constraints

Native prohibition: Do not use `Function.prototype.call`, `apply`, or `bind` internally.
Property collision safety: Use a unique `Symbol()` as the temporary property key to prevent overwriting existing keys on the context object.
Cleanup reliability: Use a `try...finally` block to guarantee the deletion of the temporary property after the function executes.
Result preservation: The return value of the original function must be captured and returned by `myCall`.

Accepted35/42|Acceptance Rate83.3%

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35. Function.prototype.call

Easy•

The Function.prototype.call() method invokes a function immediately with a specified this value and arguments passed individually.

Implement your own Function.prototype.call without using the native call, apply, or bind methods. To avoid overriding the built-in method, implement it as Function.prototype.myCall.

Example

function greet(greeting) {
  return `${greeting}, ${this.name}`;
}

const user = { name: "Alice" };

greet.myCall(user, "Hello"); // "Hello, Alice"

Constraints

Native prohibition: Do not use `Function.prototype.call`, `apply`, or `bind` internally.
Property collision safety: Use a unique `Symbol()` as the temporary property key to prevent overwriting existing keys on the context object.
Cleanup reliability: Use a `try...finally` block to guarantee the deletion of the temporary property after the function executes.
Result preservation: The return value of the original function must be captured and returned by `myCall`.

Accepted35/42|Acceptance Rate83.3%

35. Function.prototype.call

Example

Constraints

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35. Function.prototype.call

Example

Constraints

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