Räägi mulle JavaScriptis konteksti säilitamise viisidest: bind, call, apply. Kuidas nad erinevad?

In JavaScript, functions are first-class objects and have a dynamic call context (this). The methods bind, call, and apply allow managing this context:

• call — invokes the function immediately, passing the context and arguments separately.

  func.call(context, arg1, arg2);
  

• apply — similar to call, but arguments are passed as an array.

  func.apply(context, [arg1, arg2]);
  

• bind — does not invoke the function immediately, but returns a new function with the bound context and optionally partially applied arguments.

  const boundFunc = func.bind(context, arg1);
  boundFunc(arg2);
  

Differences:

• call and apply invoke the function immediately;
• bind returns a new function to be called later;
• apply is useful when arguments are already in an array;
• bind is useful for preserving context in callbacks and event handlers.