Oh look, another language (ceylon)

Chris Angelico rosuav at gmail.com
Tue Nov 19 03:54:57 CET 2013


On Tue, Nov 19, 2013 at 1:13 PM, Steven D'Aprano <steve at pearwood.info> wrote:
> On Tue, 19 Nov 2013 10:25:00 +1100, Chris Angelico wrote:
>
>> But the problem is also with strings coming back from JS.
>
> Just because you call it a "string" in Ceylon, doesn't mean you have to
> use the native Javascript string type unchanged.

Indeed not, but there are going to be many MANY cases where a JS
string has to become a Ceylon string and vice versa - a lot more often
than CPython drops to C. For instance, suppose you run your Ceylon
code inside a web browser. Pick up pretty much any piece of JavaScript
code from any web page - how much string manipulation does it do, and
how much does it call on various DOM methods? In CPython, only a small
number of Python functions will end up dropping to C APIs to do their
work (and most of those will have to do some manipulation along the
way somewhere - eg chances are print()/sys.stdout.write() will
eventually have to encode its output to 8-bit before passing it to
some byte-oriented underlying stream, so the actual representation of
a Python string doesn't matter); in browser-based work, that is
inverted.

However, Ceylon can actually be implemented on multiple backends (Java
and JavaScript listed). It's fully possible that an
"application-oriented" backend might use Pike-strings internally,
while a "browser-oriented" backend could still use the underlying
string representation. The questions are entirely of performance,
since it's been guaranteed already to have the same semantics.

I would really like to see JavaScript replaced in web browsers, since
the ECMAScript folks have stated explicitly (in response to a question
from me) that UTF-16 representation *must* stay, for backward compat.
JS is a reasonable language - it's not terrible - but it has a number
of glaring flaws. Ceylon could potentially be implemented in browsers,
using Pike-strings internally, and then someone could write a
JavaScript engine that compiles to Ceylon (complete with
bug-compatibility stupid-code that encodes all strings UTF-16 before
indexing into them). It would be an overall improvement, methinks.

ChrisA



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