Am 10.06.2014 02:18, schrieb w0rp:
I have updated the site and the repository with all of the D changelogs
split into their own pages. I had to reformat a few things, primarily
example code, so it would fit nicely in smaller column sizes. I marked
sections with headings so it fits into a table of contents. One major
thing that's missing is syntax highlighting, as I'm not sure what to use
for that.
http://w0rp.com:8010/changelog
Here is what I've noticed so far that's good about the diet templates.
1. The template syntax, taken from Jade, is easy to understand and clean.
2. I can do tricks like the table of contents easily.
However, with the good comes the bad.
1. If you are recompiling one template, you are recompiling *all* of
them. I'm getting closer to 100 templates, and it takes seconds to compile.
Sounds kind of like an ironic joke when viewed from a C++ background ;)
But yes, it's definitely not what you want to have for D. I'm not sure
how much can be done about that, though - except from rewriting the CTFE
engine with performance in mind (maybe even using a JIT compiler). Or
maybe it's possible to be more liberal with algorithmic optimizations
when the CTFE memory usage brought to a reasonable level.
2. Compiling many templates allocates like crazy during compile time and
eats memory like a hog. It takes *5GB* of RAM to compile all of these
templates.
Yes, which is why (at least with the current compiler front end) I'd
strongly recommend to put long text content in a different format that
is inserted at runtime (e.g. DDOC or Markdown).
It seems like the vibe.d diet templates take heap allocation during
compilation time way, way too far, to the point of them being
impractical to use for large websites. Somewhere around 100 templates is
something I would expect for a reasonably sized website.
It's not heap allocations. The problem is that during CTFE, currently
basically every variable change allocates memory that is never freed
again. I've used a few tricks to get the memory usage down (which is why
the Diet compiler source code doesn't look very pretty), but basically
the only way to get reasonable memory use is to fix the D front end.
So I have a plea or two for vibe.d
In addition to recompiling diet templates automatically during
development, which has been mentioned before, I believe there should be
an option to defer compilation of a template the first time, during
development, until you view a page using it for the first time. This
woud solve the slower compilation issue, because then you'd only pay for
what you used.
That would probably even be a side-effect of the implementation of
separately compiled templates (eagerly compiling them will require some
additional code).
Second, something must be done about memory allocation during
compilation of diet templates. There's too much going on there.
That's it for now.
See also https://issues.dlang.org/show_bug.cgi?id=6498
