call() , apply() , & bind() functions ??

In JavaScript, functions are first-class objects, and they come with built-in methods that allow us to control how and where they are executed. Three such methods are call, apply, and bind. These methods let us set the value of this inside a function and can be very handy in various scenarios.

?? They are useful for borrowing methods from other objects and writing less code.

call()??

The call method lets you call a function with a specific this value and arguments one by one.

? Syntax:? functionName.call(thisValue, arg1, arg2, ...);

? Explanation

• thisValue: The object you want this to refer to inside the function.
• arg1, arg2, ...: The arguments you want to pass to the function.

apply()??

The apply method is similar to call, but it takes the arguments as an array.

? Syntax : functionName.apply(thisValue, [argsArray]);

? Explanation

• thisValue: The object you want this to refer to inside the function.
• [argsArray]: An array of arguments you want to pass to the function.

?? Important: The only difference between apply and call is that apply takes an array of arguments. Both call and apply invoke the function immediately.

bind()??

The bind method creates a new function that, when called, has its this value set to the specified value, and can have some arguments preset.

? Syntax : const boundFunction = functionName.bind(thisValue, arg1, arg2, ...);

? Explanation

• thisValue: The object you want this to refer to inside the new function.
• arg1, arg2, ...: The arguments you want to preset for the new function.

?? Major Difference: Unlike call and apply, which invoke the function immediately, bind returns a new function that you can call later.

Conclusion ??

?? call lets you call a function with a specific this value and arguments provided one by one.

?? apply is similar but takes the arguments as an array.

?? bind creates a new function with a specific this value and optionally preset arguments.

Differences:

?? Invocation: call and apply invoke the function immediately, while bind returns a new function for later invocation.

?? Arguments: call takes arguments individually, whereas apply takes arguments as an array.

?? Usage: bind is useful when you need a function to be called later with a specific this value and preset arguments, while call and apply are used to invoke functions immediately with a specific this value.

?? These methods help you control the context (this value) of your functions, making your code more flexible and reusable.

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