On my machine (Mac OSX Lion), the Python code clocks around 1.2 seconds
and the D code at a whopping 9.3 seconds. I looked around where the
problem lies and sure enough the issue was with a slow loop in the
generic I/O implementation of readln. The commit
https://github.com/D-Programming-Language/phobos/commit/94b21d38d16e075d7c44b53015eb1113854424d0
brings the speed of the test to 2.1 seconds. We could and should reduce
that further with taking buffering in our own hands, but for now this is
a good low-hanging fruit to pick.
Nice, I just got shocked yesterday by seeing that we call fgetc for every
char,
those are usually macros and as we already maintain the per system
*_unlocked
functions we might probably use the macro expansions.
