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You cannot. bar is called before the object is constructed, obj will be undefined and the already-evaluated values of the previous properties (1 and 2) are somewhere inaccessible in memory only. See also Self-references in object literals / initializers.

Given you found this question in a quiz with pretty arbitrary restrictions, they seem to expect a trick answer. There are several ways:

• Access to source code and evaluate the object literal yourself

• Simply return a constant, given that obj.x and obj.y are constant in the given code as well

• Overwrite console.log to do your bidding, for example

    function bar() {
        var log = console.log.bind(console);
        console.log = function(p) {
            log(p.valueOf());
        };
        return {
            valueOf: function() {
                return obj.x + obj.y;
            }
        };
    }
  

  Doesn't work unfortunately due to console.log being dereferenced before foo() is called.
  A similar approach does work in environments where the console.log behaviour can be customized without needing to overwrite anything:

    function bar() {
        return {
            inspect: function() {
                return String(obj.x + obj.y);
            }
        };
    }
  

• Just call foo() yourself to get the values, but don't recurse infinitely on bar:

    function bar() {
        if (foo.stop) return null;
        foo.stop = true;
        var res = foo().x + foo().y;
        foo.stop = false;
        return res;
    }
  

You cannot. bar is called before the object is constructed, obj will be undefined and the already-evaluated values of the previous properties (1 and 2) are somewhere inaccessible in memory only. See also Self-references in object literals / initializers.

Given you found this question in a quiz with pretty arbitrary restrictions, they seem to expect a trick answer. There are several ways:

• Access to source code and evaluate the object literal yourself

• Simply return a constant, given that obj.x and obj.y are constant in the given code as well

• Overwrite console.log to do your bidding, for example

    function bar() {
        var log = console.log.bind(console);
        console.log = function(p) {
            log(p.valueOf());
        };
        return {
            valueOf: function() {
                return obj.x + obj.y;
            }
        };
    }
  

  Doesn't work unfortunately due to console.log being dereferenced before foo() is called.
  A similar approach does work in environments where the console.log behaviour can be customized without needing to overwrite anything:

    function bar() {
        return {
            inspect: function() {
                return String(obj.x + obj.y);
            }
        };
    }
  

• Just call foo() yourself to get the values, but don't recurse infinitely on bar:

    function bar() {
        if (foo.stop) return null;
        foo.stop = true;
        var res = foo().x + foo().y;
        foo.stop = false;
        return res;
    }
  

You cannot. bar is called before the object is constructed, obj will be undefined and the already-evaluated values of the previous properties (1 and 2) are somewhere inaccessible in memory only. See also Self-references in object literals / initializers.

Given you found this question in a quiz with pretty arbitrary restrictions, they seem to expect a trick answer. There are several ways:

• Access to source code and evaluate the object literal yourself

• Simply return a constant, given that obj.x and obj.y are constant in the given code as well

• Overwrite console.log to do your bidding, for example

    function bar() {
        var log = console.log.bind(console);
        console.log = function(p) {
            log(p.valueOf());
        };
        return {
            valueOf: function() {
                return obj.x + obj.y;
            }
        };
    }
  

  Doesn't work unfortunately due to console.log being dereferenced before foo() is called.

• Just call foo() yourself to get the values, but don't recurse infinitely on bar:

    function bar() {
        if (foo.stop) return null;
        foo.stop = true;
        var res = foo().x + foo().y;
        foo.stop = false;
        return res;
    }
  

You cannot. bar is called before the object is constructed, obj will be undefined and the already-evaluated values of the previous properties (1 and 2) are somewhere inaccessible in memory only. See also Self-references in object literals / initializers.

Given you found this question in a quiz with pretty arbitrary restrictions, they seem to expect a trick answer. There are several ways:

• Access to source code and evaluate the object literal yourself

• Simply return a constant, given that obj.x and obj.y are constant in the given code as well

• Overwrite console.log to do your bidding, for example

    function bar() {
        var log = console.log.bind(console);
        console.log = function(p) {
            log(p.valueOf());
        };
        return {
            valueOf: function() {
                return obj.x + obj.y;
            }
        };
    }
  

  Doesn't work unfortunately due to console.log being dereferenced before foo() is called.
  A similar approach does work in environments where the console.log behaviour can be customized without needing to overwrite anything:

    function bar() {
        return {
            inspect: function() {
                return String(obj.x + obj.y);
            }
        };
    }
  

• Just call foo() yourself to get the values, but don't recurse infinitely on bar:

    function bar() {
        if (foo.stop) return null;
        foo.stop = true;
        var res = foo().x + foo().y;
        foo.stop = false;
        return res;
    }
  

You cannot. bar is called before the object is constructed, obj will be undefined and the already-evaluated values of the previous properties (1 and 2) are somewhere inaccessible in memory only. See also Self-references in object literals / initializers.

Given you found this question in a quiz with pretty arbitrary restrictions, they seem to expect a trick answer. There are several ways:

• Access to source code and evaluate the object literal yourself

• Simply return a constant, given that obj.x and obj.y are constant in the given code as well

• Overwrite console.log to do your bidding, for example

    function bar() {
        var log = console.log.bind(console);
        console.log = function(p) {
            log(p.valueOf());
        };
        return {
            valueOf: function() {
                return obj.x + obj.y;
            }
        }
    }
  

You cannot. bar is called before the object is constructed, obj will be undefined and the already-evaluated values of the previous properties (1 and 2) are somewhere inaccessible in memory only. See also Self-references in object literals / initializers.

Given you found this question in a quiz with pretty arbitrary restrictions, they seem to expect a trick answer. There are several ways:

• Access to source code and evaluate the object literal yourself

• Simply return a constant, given that obj.x and obj.y are constant in the given code as well

• Overwrite console.log to do your bidding, for example

    function bar() {
        var log = console.log.bind(console);
        console.log = function(p) {
            log(p.valueOf());
        };
        return {
            valueOf: function() {
                return obj.x + obj.y;
            }
        };
    }
  

  Doesn't work unfortunately due to console.log being dereferenced before foo() is called.

• Just call foo() yourself to get the values, but don't recurse infinitely on bar:

    function bar() {
        if (foo.stop) return null;
        foo.stop = true;
        var res = foo().x + foo().y;
        foo.stop = false;
        return res;
    }