On Saturday, 24 December 2016 at 09:34:03 UTC, Andrei
Alexandrescu wrote:
(I confirm that importing std.traits, std.meta, and
std.range.primitives together takes 10ms.)
while compiling std.traits 6 files are opened and read into
memory,
taking roughly 300 microseconds, which is not even 0.3% of the
time spent.
Lexing them requires additionally also about 300 microseconds.
So Together that makes up 0.6% of the time spent.
The real problem here is _NOT_ opening and lexing files.
It is rather eager parsing and sema.
If that were made more lazy, we could import half of the world
with noticing impact.
(Which espcially in std.traits, would not make that much of a
difference since every template in there depends on nearly every
other template in there)
