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isString ​

Checks if the given value is a string.

This function can also serve as a type predicate in TypeScript, narrowing the type of the argument to string.

Signature ​

typescript
function isString(value: unknown): value is string;

Parameters ​

  • value(unknown): The value to test if it is string.

Returns ​

  • (x is string): True if the value is a string, otherwise false.

Examples ​

typescript
const value1 = 'abc';
const value2 = 123;
const value3 = true;

console.log(isString(value1)); // true
console.log(isString(value2)); // false
console.log(isString(value3)); // false

Released under the MIT License.