_.isString(value) source npm package Checks if value is classified as a String primitive or object. Since 0.1.0 Arguments value (*): The value to check. Returns (boolean): Returns true if value is a string, else false. Example _.isString('abc'); // => true   _.isString(1); // => false

_.isSet(value) source npm package Checks if value is classified as a Set object. Since 4.3.0 Arguments value (*): The value to check. Returns (boolean): Returns true if value is a set, else false. Example _.isSet(new Set); // => true   _.isSet(new WeakSet); // => false

_.isSafeInteger(value) source npm package Checks if value is a safe integer. An integer is safe if it's an IEEE-754 double precision number which isn't the result of a rounded unsafe integer.Note: This method is based on Number.isSafeInteger. Since 4.0.0 Arguments value (*): The value to check. Returns (boolean): Returns true if value is a safe integer, else false. Example _.isSafeInteger(3); // => true   _.isSafeInteger(Number.MIN_VALUE); // => false   _.isSafeInteger(Infinity); // =

_.isRegExp(value) source npm package Checks if value is classified as a RegExp object. Since 0.1.0 Arguments value (*): The value to check. Returns (boolean): Returns true if value is a regexp, else false. Example _.isRegExp(/abc/); // => true   _.isRegExp('/abc/'); // => false

_.isPlainObject(value) source npm package Checks if value is a plain object, that is, an object created by the Object constructor or one with a [[Prototype]] of null. Since 0.8.0 Arguments value (*): The value to check. Returns (boolean): Returns true if value is a plain object, else false. Example function Foo() {   this.a = 1; }   _.isPlainObject(new Foo); // => false   _.isPlainObject([1, 2, 3]); // => false   _.isPlainObject({ 'x': 0, 'y': 0 }); // => true   _.isPlainObject(Obj

_.isObjectLike(value) source npm package Checks if value is object-like. A value is object-like if it's not null and has a typeof result of "object". Since 4.0.0 Arguments value (*): The value to check. Returns (boolean): Returns true if value is object-like, else false. Example _.isObjectLike({}); // => true   _.isObjectLike([1, 2, 3]); // => true   _.isObjectLike(_.noop); // => false   _.isObjectLike(null); // => false

_.isObject(value) source npm package Checks if value is the language type of Object. (e.g. arrays, functions, objects, regexes, new Number(0), and new String('')) Since 0.1.0 Arguments value (*): The value to check. Returns (boolean): Returns true if value is an object, else false. Example _.isObject({}); // => true   _.isObject([1, 2, 3]); // => true   _.isObject(_.noop); // => true   _.isObject(null); // => false

_.isNumber(value) source npm package Checks if value is classified as a Number primitive or object.Note: To exclude Infinity, -Infinity, and NaN, which are classified as numbers, use the _.isFinite method. Since 0.1.0 Arguments value (*): The value to check. Returns (boolean): Returns true if value is a number, else false. Example _.isNumber(3); // => true   _.isNumber(Number.MIN_VALUE); // => true   _.isNumber(Infinity); // => true   _.isNumber('3'); // => false

_.isNull(value) source npm package Checks if value is null. Since 0.1.0 Arguments value (*): The value to check. Returns (boolean): Returns true if value is null, else false. Example _.isNull(null); // => true   _.isNull(void 0); // => false

_.isNil(value) source npm package Checks if value is null or undefined. Since 4.0.0 Arguments value (*): The value to check. Returns (boolean): Returns true if value is nullish, else false. Example _.isNil(null); // => true   _.isNil(void 0); // => true   _.isNil(NaN); // => false