Instruction: Describe the differences between function expressions and function declarations in JavaScript.
Context: This question tests the candidate's understanding of function scope, hoisting, and the nuances of function usage in JavaScript.
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First, let's clarify the concepts. In JavaScript, functions can be defined in several ways, but the two most common methods are through function declarations and function expressions. Both approaches define functions, but they have key differences in their behavior, particularly concerning hoisting and scope.
A function declaration is the more traditional way to define a function. It starts with the function keyword, followed by the name of the function, a list of parameters enclosed in parentheses, and then the function body enclosed in curly braces. For instance: function add(a, b) { return a + b; } One significant strength of function declarations is their hoistability. This means that function declarations are hoisted to the top of their enclosing scope, whether that's the global scope or a function scope. Thus, they can be...