How about colors and terminal graphics in std.format?

[Adam D. Ruppe]

One concern I have with this is format() creates a
string, which isn't necessarily output; color is
a thing of output.

The unix implementation will use the ansi escape
sequences, surely, which isn't correct almost
anywhere else.

Of course, you could choose to not use these
special specifiers, and put a note in the
documentation explaining what it is, so
not a big deal... but I just think it is
somewhat wrong to put special control
sequences in the middle of a regular string
that might be used anywhere.