Module json

Type guards for JSON values.

Provides predicates to validate and narrow values to JSON-compatible types, supporting safe operations on serializable data.

import { isBoolean, isNumber, isString, isScalar, isObject, isArray, isEmpty, isJSON } from '@metreeca/core';

isValue({ a: [1, 2], b: "test" }); // true
isValue({ a: new Date() }); // false

isScalar(42); // true
isScalar([1, 2]); // false

isBoolean(true); // true
isNumber(42); // true (excludes NaN, Infinity)
isString('hello'); // true

isArray([1, 2, 3], isNumber); // true
isArray([1, 'two'], isNumber); // false

isObject({ a: 1 }); // true
isObject(new Date()); // false

isEmpty([]); // true
isEmpty({ a: 1 }); // false

See

RFC 8259 - The JavaScript Object Notation (JSON) Data Interchange Format

Type Aliases

Value: Immutable JSON value.
Array: Immutable JSON array.
Object: Immutable JSON object.

Functions

isValue: Checks if a value is a valid JSON value.
isScalar: Checks if a value is a scalar.
isNull: Checks if a value is null.
isBoolean: Checks if a value is a boolean.
isNumber: Checks if a value is a finite number.
isString: Checks if a value is a string.
isArray: Checks if a value is an array.
isObject: Checks if a value is a plain object.
isEmpty: Checks if a value is an empty plain object or an empty array.

Module json

See

Type Aliases

Functions

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