export function isFunction(val) {
  return typeof val === 'function';
}

export const isString = val => typeof val === 'string';

export const isNull = value => value === null;

export const isUndefined = value => value === undefined;

export function isDef(value) {
  return !isUndefined(value) && !isNull(value);
}

export function isInteger(value) {
  return Number.isInteger(value);
}

export function isNumeric(value) {
  return !Number.isNaN(Number(value));
}

export function isNumber(value) {
  return typeof value === 'number';
}

export function isBoolean(value) {
  return typeof value === 'boolean';
}

export function isObject(x) {
  const type = typeof x;
  return x !== null && (type === 'object' || type === 'function');
}

export function isPlainObject(val) {
  return val !== null && typeof val === 'object' && Object.prototype.toString.call(val) === '[object Object]';
}