LeaVerou
repeating
I think there should be a function that repeats last called method.
An alternative to your roundRect function:
function roundRect(x, y, w, h, r) { w+=x; h+=y; return this.beginPath().moveTo(x + r, y) .arcTo(w, y, w, h, r).re(w, h, x, h, r) .re(x, h, x, y, r).re(x, y, w, y, r).closePath(); }
the "re" function is a build-in function always point to last method, here i.e. arcTo.
Should it be a feature that saves the chains ......and reuse it. It is achievable by Function.bind()?
I’m afraid that’s not technically possible in a robust way. To make functions chainable, chainvas just returns this. There is no wrapper (like jQuery), so it’s impossible to store that kind of information.
The only way I can think of is to store the function in a property of the Chainvas object, and have .re call that. However, that could lead in unpredictable results in cases where it's used on different contexts, like:
element.setAttribute('foo', 'bar');
canvasCtx.re(...); // Equivalent to canvasCtx.setAttribute(...), which makes no sense
That would also introduce some overhead, as every method call should store a reference to itself in that property, just so that re could use it.
Of course, it's entirely possible that there's a better solution I'm just not seeing.
If you focus on canvas, the "re" function is useful (for lazy persons).
I add a line in the chainable function:
chainable: function(method) { return function() { var ret = method.apply(this, arguments); this.re=arguments.callee; // * return ret === undefined? this : ret;
However, using callee is not allowed in strict mode.
And BTW, the roundRect using arcTo in Opera is not correctly shown.
Right, that cleverly solves one of the issues I mentioned, but not the other (overhead).
I see the problem that adding a "re" property to the object may not be useful, especially the DOM interfaces.
I have an idea actually I used. It is a mix of function and object. See http://bbs.51js.com/thread-90256-1-1.html