Well yah, if you inconsistently format the javascript of course pyscript will come out better.

// Javascript
function triangle(a,b) {
if(a > 0 && b > 0 ) {
function sqroot(x) {
return (x > 0) ? Math.pow(x,.5) : 0;
}
return sqroot( a*a + b*b );
} else return 0;
}

// mozilla specific
function triangle(a,b) {
if(a > 0 && b > 0 ) {
function sqroot(x) (x > 0) ? Math.pow(x,.5) : 0;
return sqroot( a*a + b*b );
} else return 0;
}

// or even better
// Javascript
function triangle(a,b) {
if (a < 0 || b 0) ? Math.pow(x,.5) : 0;
return sqroot( a*a + b*b );
}

well it broked my comment again here is the gist anyway

http://gist.github.com/277650

I’m going to guess you’ve seen CoffeeScript (since I know you read Reddit), but just in case…

It has a similar sort of goal – making the JavaScript syntax more beautiful. It’s not trying to imitate Python syntax (that I’m aware of), but could give you some interesting ideas. I don’t think it’s as easy as you’re making this, but still cool.

Some of the syntax improvements already exist! Version 1.7 of JavaScript is available today, in some modern browsers, and the changes thru 1.8.1 are worth reviewing.

https://developer.mozilla.org/en/New_in_JavaScript_1.6
https://developer.mozilla.org/en/New_in_JavaScript_1.7
https://developer.mozilla.org/en/New_in_JavaScript_1.8
https://developer.mozilla.org/En/New_in_JavaScript_1.8.1

How do anonymous functions work in this syntax? Pythonizing javascript is an excellent idea but one of the big differences at least in python proper is the lack of multiline anonymous functions which I use quite frequently in javascript.

For example:
doIt(function (thingeroo) {
/* do something complicated and
interesting here */
});

Can not be done in python unless you name the function which can be useful but then it creates a sort of visual break in the flow of the code that can look awkward.

I’ve always found Python’s whitespace-based block formatting to be a shortcoming of the language.

With curly braces, you can easily count the closing braces to see how many levels you’ve just closed.

Whitespace indentation levels are much more difficult to visually count, unless you move your caret around and count the steps that way. You could set your text editor to show markers for each indentation, but then your screen becomes more cluttered with symbols than it is with JavaScript.

Overall, I’m a fan of JavaScript’s syntax. There are some problems, such as semicolon inference (which can eventually be disabled using the new “strict” feature in ECMAScript 5), but it’s mostly a very nice syntax to work with.

My main complaint about JavaScript is the rather poor standard library. Compared with something like PHP, which comes standard with hundreds of useful functions for working with basic data types (strings, arrays, dates/times, etc.), JavaScript’s offer feels very incomplete. No native base64 encoding/decoding, no equivalent of htmlspecialchars or htmlentities, no native support for sorting an array numerically or in natural language order (PHP’s natsort), and on and on. I know these features can be implemented through custom JavaScript code or external libraries, but that shouldn’t be necessary for this kind of basic stuff.

At any rate, I supposed the syntax thing is a largely subjective issue. I think your JavaScript example is more readable than the PyScript example (although your inline whitespace usage was inconsistent in both examples). But, arguing meaningful indentation vs. visual delimiters is like arguing spaces vs. tabs for indentation: Tabs are better, and no one can tell me otherwise. ;)

Neat bit of work, Aza.

That said, if you figure out a workable syntax for anonymous functions, you might finally be able to convince Guido. People have been trying for a while to figure out how to anonymous functions work right in Python.

You should preserve any extra flags in the “pyscript” type in your `evalPyscript` function.

The relavent code would be the following. You would only want to replace the first pyscript so a string is going to be more appropriate than a regexp.

s.type = scripts[i].type.replace(“pyscript”, “javascript”)

For example, this will allow you to use “application/x-pyscript;version=1.8″ to use JavaScript 1.8 and higher features.

Also, JavaScript 1.8 has similar implicit brackets but also implicit return statements for functions so you can do the following:

function foo (bar, baz) bar + baz

I personally think the pyscript should be converted to javascript using a command line tool.

That way, you wouldn’t have to parse the code every time you run it.

Aza — please do take a peek at CoffeeScript when you get a chance. It’s a stab at trying to answer the questions that you raise here, and includes function literals that clear out the clutter. To square a number:

x => x * x

Passing a function into a function call:

elements.each(el => el.show())

Or, using block-style syntax:

numbers.reduce(0) sum, num =>
sum + num

Finally, the empty function:

=>

The most interesting thing about it is that all JavaScript statements are transformed into expressions (via closures, when necessary), so you can add up assignments, pass try/catch or if/else as an argument, and assign to the result of an if statement.

PyScript is nice and short and sweet right now, but I’m sure there’s plenty of room for it to grow — we should all be cross-pollinating as much as possible…

Would this be just for development, or would files be served to the browser like this too? Or would they be “compiled” back to JS?

JavaScript is an interesting language, because the code is both seen by the programmer and sent to the user.

How well would this minify? Removing {} saves some bandwidth, but there’d be lots of whitespace.

Would there ever be issues with servers using different line endings (\r\n)? Would JSON work ok?

That pointless “else: return 0″ instead of just “return 0″ at the end is just there to make the old style look bad, right?

Yeah, Aza, seems you’ve been in Python too long, you can’t write concise javascript anymore.

Alternatively, you’re deliberately writing excessively verbose JavaScript to make PyScript seem better in comparison. Can’t be that, right?

Also, readable and pythonic are not synonymous.

My eyes! The goggles do nothing!

I love python’s syntax, but at the same time I think your example does brackets and braces a disservice.

Here’s an example with much better formatting consistency (pastebined because it seems this blog will chew up the formatting): http://pastie.org/779716

Once you add more consistent formatting, and follow the guard pattern, the code looks much cleaner and more comparable.

Personally, with braces I can take or leave it. I like that they’re not needed in Python, but I don’t find them terribly egregious when they are.

I do, however, actually like the brackets around conditions. It’s probably just familiarity, but for some reason I find it much easier to read a condition when it is in brackets — to see where it begins and ends. I know logically that is weird and is likely not the same for other people, but it still feels awkward to read python without the brackets.

This can’t possibly be any good for JavaScript performance. Instead of obfuscating JavaScript, why not just learn JavaScript and stick to it? It’s much easier for everyone involved. I seriously hope that nobody tries to start a serious web development project using Pyscript. Pyscript is only dithering the usefulness and ubiquity of JavaScript.

Personally, I find that the braces force less visual complexity per line, since they typically force mostly-blank lines. Of course, I also like spaces after parens in function declarations, and spaces after commas – just more spaces in general. I also wish JS had mandatory semicolons, instead of this crazy guessing that is mostly, but not always, right…

It is interesting to note that your pythonic javascript would fail horrendously in your blog comments due to indents being stripped completely.

Your examples look almost like valid python, with s/function/def/ and removing the various variable declarations. Perhaps what you _actually_ want is to build on ActiveState’s pyxpcom/pydom work and use Real Python in the browser instead?

“While I’ve come to love Javascript”

Well, THERE’s yaahr prahblem. :)

Javascript with slightly more Pythonic syntax? Why? The only benefit Javascript has over Python is that it doesn’t rely on indentation and therefore can be compacted. You just removed Javascripts only benefit as a browser language. If you want indentation (and I do) then why not just go full out to Python?

really such scripts will not be able to reduce in volume:). This is the loss advantage of this approach!

Really? I think this makes it worse as far as readability. Can’t tell who’s nested where. Just use a text editor with syntax highlighting and code-collapse and JS is easily readable.

Doesn’t that triangle function just boil down to the Javascript below?

function triangle(a, b) {
return Math.min(a, b) <= 0 ? Math.pow(a * a + b * b, 0.5) : 0;
}

Not having any experience with Python, I can’t really tell where code blocks begin and end in your examples. For instance, take your second example:

// Example Two
for var i=0; i<5; i++:
var el = document.getElementById(“el”+i)
if count % 2 == 0:
el.innerHTML = “Hello”
else:
el.innerHTML = “World”

How do I know the if…else block is inside the loop? Of course, I can guess based on the scope of “el”, but that reasoning is not based in any way on the syntax.

Honestly, it would be easier to read VBScript:

For i = 0 to 4
Dim el = document.getElementById(“el” + i)

If count Mod 2 = 0 Then
el.innerHTML = “Hello”
Else
el.innerHTML = “World”
End If
Next i

Er, has anyone done a Google for Pyscript lately? There seems to be another project called Pyscript. Let’s all get confused.

Hello. Thank you for sharing your post. I’m sure your readers who are web enthusiasts as well will be very interested in this. Looking forward to reading more of your posts. All the best.

I don’t think I’ve come across a blog without any timestamps (or at least dates) before. Frustrating, to say the least.

I do love the idea of this though! I just can’t tell if it’s been around long enough for me to have missed it when I looked around a few months ago ;)

Hello, would you mind if I use some of your sites content on http:/basicwebdesign.co.cc ? I’ll be sure to keep the credit to you, along with a link back to your site. Thanks.

Tebrikler vallahi dua edeceksiniz bana.

My eyes! The goggles do nothing.

I used to think this about JavaScript when I first switched to if from Ruby, but I’ve grown to like the old girl and now it’s Ruby that looks unpleasant to my eyes.

I guess there’s no accounting for taste!