Issue 6448 - writef("%05d", BigInt) problem

[9rnsr]

http://d.puremagic.com/issues/show_bug.cgi?id=6448

BigInt should understand format specifiers ('d', 'x', 'X', 's') just like integers.

Limitation:
The formatting of negative BigInt as hexadecimal is different from built-in integers, because of their internal representations (Two's complement vs sign and absolute).

[donc]

This is great, except there's one thing I really dislike (though it is currently inevitable): it creates a dependency on std.format, and therefore on about 20 other Phobos modules. Up until now, BigInt has been one of the few parts of Phobos that hasn't been part of the big ball of mud. I hope that we'll be able to pull FormatSpec out of std.format eventually. To make that more achievable, can you turn the import into a static import, please?

[9rnsr]

To make that more achievable, can you turn the import into a static import, please?

Now std.format is already imported with private, then it is not visible from other modules. Is it really necessary?

[donc]

Great. Please also change the import at the top (line 28):

• private import std.format;
  +private import std.format : FormatSpec, FormatError, formattedWrite;
  and I'll merge it in. (When I said "static import" before, I meant to say "selective import". Makes maintenance easier).
  Note that when we eventually do accurate output of floating-point numbers, std.format is likely to require BigInt, so this may become part of a circular import.

[9rnsr]

OK, I have done it. Thanks, Don!