infinite stream in JS

inifinite.stream.js

// Infite stream implementation with Basic promises.

// inspired by
// http://perl.plover.com/Stream/stream.html#streams

var Stream = function(_head, _tail) {
    this.h = _head;
    this.t = _tail;
};

Stream.prototype.head = function() {
    return this.h;
}

Stream.prototype.tail = function() {
    var _tail = this.t;
    if (_tail instanceof Function) {
        console.log('call tail promise');
        this.t = _tail();
    }

    return this.t;
}

Stream.prototype.show = function(len) {
    var cpos = 0;
    var self = this;

    do {
        console.log('element', cpos, ':', self.head());
        self = self.tail();
        cpos++;
    } while(cpos < len);
}

// --- code now ---

function tabulate (f, n) {
    console.log('instance of new Stream...');

    return new Stream(
        f(n), function() {
            return tabulate(f, n + 1);
        }
    );
}

var square = function(a) {
    return a * a;
}

console.log('tabulate...');
squares = new tabulate(square, 1);

console.log('show stream...');
squares.show(5);
squares.show(3);