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What does the typeof function do?

User Aorr
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The typeof function in JavaScript is used to determine the data type of a variable. It returns a string indicating the type of the operand, such as 'string', 'number', or 'boolean'. This aids in debugging and ensuring that operations on variables are type-appropriate.

The typeof function in JavaScript is an operator that returns a string indicating the type of the unevaluated operand, or the type of value. In other words, it tells you what type of data a variable is, such as string, number, boolean, undefined, object, function, or symbol. This is particularly useful for debugging or for determining the type of a value before performing a specific operation on it. For instance, you might use typeof in an if statement to determine if a variable is a string before trying to manipulate it with string-specific methods.

  • typeof "hello"; // "string"
  • typeof 42; // "number"
  • typeof true; // "boolean"

typeof is a very handy function for identifying the type of values in JavaScript which aids developers in writing accurate and bug-free code by assuring the correct types are used.

User BurpmanJunior
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