code: function booleanAssertions(should, Assertion) {
    /**
     * Assert given object is exactly `true`.
     *
     * @name true
     * @memberOf Assertion
     * @category assertion bool
     * @alias Assertion#True
     * @param {string} [message] Optional message
     * @example
     *
     * (true).should.be.true();
     * false.should.not.be.true();
     *
     * ({ a: 10}).should.not.be.true();
     */
    Assertion.add("true", function(message) {
      this.is.exactly(true, message);
    });
  
    Assertion.alias("true", "True");
  
    /**
     * Assert given object is exactly `false`.
     *
     * @name false
     * @memberOf Assertion
     * @category assertion bool
     * @alias Assertion#False
     * @param {string} [message] Optional message
     * @example
     *
     * (true).should.not.be.false();
     * false.should.be.false();
     */
    Assertion.add("false", function(message) {
      this.is.exactly(false, message);
    });
  
    Assertion.alias("false", "False");
  
    /**
     * Assert given object is truthy according javascript type conversions.
     *
     * @name ok
     * @memberOf Assertion
     * @category assertion bool
     * @example
     *
     * (true).should.be.ok();
     * ''.should.not.be.ok();
     * should(null).not.be.ok();
     * should(void 0).not.be.ok();
     *
     * (10).should.be.ok();
     * (0).should.not.be.ok();
     */
    Assertion.add("ok", function() {
      this.assertZeroArguments(arguments);
      this.params = { operator: "to be truthy" };
  
      this.assert(this.obj);
    });
  }
docs: /*
  should.js - assertion library
  Copyright(c) 2010-2013 TJ Holowaychuk <tj@vision-media.ca>
  Copyright(c) 2013-2017 Denis Bardadym <bardadymchik@gmail.com>
  MIT Licensed