On Wednesday, 20 February 2013 at 22:34:15 UTC, Andrej Mitrovic
wrote:
On 2/20/13, David Nadlinger <[email protected]> wrote:
In Phobos, there are quite a few unit tests (std.format,
std.json, ...) which assume that the %e floating point format
zero-pads the exponent to (at least) two digits.
I don't know about the exponent problem, but w.r.t. floating
point
there was a recent bug fixed where this source file:
auto x = 1.0;
Would be converted to this header file:
auto x = 1;
These are then different types. So I've changed how
floating-point is
written in DMD to always emit "1.0" rather than "1". This also
improved diagnostics.%
But I wanted to always print at most two digits in this case
(e.g.
1.00, 2.00, etc) but couldn't find a good way to do it with
sprintf,
so currently for floating-point e.g. "1" it prints "1.00000" in
diagnostics and header files, which is excessive.
Anyway I would definitely like to see floating-point printing
synchronized across multiple compilers and also the D library,
to be
consistent everywhere.
Another related issue is the format of %a. On Windows it prints
0x1.444p+99
but on Linux the same number is
0x0.A22p+99
That's much easier to deal with, because it's trivial to print
the %A format.
Correctly-rounded %e, %f is much more difficult, unfortunately
(you need some
simple bigint arithmetic).
