[devinus]

This is interesting. Since it's hard to read, I've extracted the language statistics and I'll leave them here:

C# - 7.9% C - 7.2% Rust - 7.1% Visual - Basic - 6.6% Makefile - 6.5% Java - 5.8% Forth - 5.0% Go - 4.5% PostScript - 4.2% Haskell - 4.0% Shell - 3.8% Perl - 3.5% JavaScript - 3.4% Matlab - 3.2% Scala - 3.1% PHP - 3.1% OCaml - 3.0% Lua - 2.8% R - 2.7% Python - 2.7% CoffeeScript - 1.9% Ruby - 1.9% Clojure - 1.9% Scheme - 1.7% CSS - 1.4% Other - 1.1%

It seems you could extrapolate interesting theories regarding productivity using these numbers.

There's a jump between Ruby/CoffeeScript and Python, and I wonder why.

[barrkel]

The fact that C# came out with 36% more lines than Java would make me doubt much extrapolation about productivity from these numbers. You can do a token for token substitution of Java and end up with close to compilable C# code; there are only a handful of things Java has that C# doesn't, while C# has many more abstraction tools.

[Veedrac]

This is just because Java is using `readline` and C# is reimplementing it AFAICT.

[zatkin]

I'm willing to bet that most of the Java code could be made shorter with the use of more functional style code in Java 1.8 (which might be why he labeled it "Java 1.7")

[edgyswingset]

Yep. Things like this:

https://github.com/kanaka/mal/blob/master/cs/core.cs#L272

Could easily be turned into one line ... not that any sane person would want to, though.

[Veedrac]

I was curious about this, so here is the result of my digging.

`core` has inline lambdas in Ruby:

    :prn =>       lambda {|*a| puts(a.map {|e| _pr_str(e, true)}.join(" "))},

but separately defined ones in Python

    def prn(*args):
        print(" ".join(map(lambda exp: printer._pr_str(exp, True), args)))
        return None

    ...

    'prn': prn,

Note that `return None` isn't needed - Ruby doesn't have it, so that's a "wasted" line. The function should also be more like

    def prn(*args):
        print(" ".join(printer._pr_str(exp, True) for exp in args))

or, if Python 2 support wasn't needed,

    def prn(*args):
        print(*(printer._pr_str(exp, True) for exp in args))

Defining these out-of-line is a good idea, though (it improves introspection in Python).

`mal_readline` has a bit of support for Python 2 which takes a few lines, but mostly it's code like

    try:
        with open(histfile, "r") as hf:
            for line in hf.readlines():
                pyreadline.add_history(line.rstrip("\r\n"))
                pass
    except IOError:
        print("Could not open %s" % histfile)
        pass

versus

    File.readlines($histfile).each {|l| Readline::HISTORY.push(l.chomp)}

The Python code handles errors but has two pointless `pass` statements and a couple of odd choices. It should better be:

    try:
        with open(histfile) as hf:
            for line in hf:
                pyreadline.add_history(line.rstrip("\n"))
    except IOError:
        print("Could not open %s" % histfile)

Note that the Python uses lazy reading which is why it needs explicit closing; Ruby likely would too if it read lazily.

I have no idea what's up with `mal_types`/`types`; Ruby does simple stuff and then Python does... something. I will say that the Python can be a lot simpler at minimum, although I'd need to grok what it does before I can say what. For example,

    elif _hash_map_Q(a):
        akeys = a.keys()
        akeys.sort()
        bkeys = b.keys()
        bkeys.sort()
        if len(akeys) != len(bkeys): return False
        for i in range(len(akeys)):
            if akeys[i] != bkeys[i]: return False
            if not equal_Q(a[akeys[i]], b[bkeys[i]]): return False
        return True

can be replaced with

    elif type(a) is Hash_Map:
        return a.keys() == b.keys() and all(equal_Q(val, b[key]) for key, val in a.items())

I think the `_Q` suffix is a the writer missing Ruby's `?`-suffixes on identifiers.

There's also a lot of mess that I think arises because the writer might not be aware that you can make callable objects in Python.

I think in the end it comes down to language experience. My Ruby would probably look as hacky as Joel Martin's Python. I doubt there would be as large a difference if they were both written with the same language familiarity.

[agumonkey]

I guess it's really hard to be idiomatic in 23 languages.

[kanaka]

Python is one of the oldest implementations and I ought to do a another pass through to clean it up sometime.

I'm happy to take pull requests that make an implementation shorter and/or more idiomatic as long as it doesn't change the overall order/flow (and doesn't break any of the tests of course).