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From: Karl Nelson (kenelson_at_[hidden])
Date: 2002-02-19 12:05:13

> On 2/12/02 11:07 AM, "Karl Nelson" <kenelson_at_[hidden]> wrote:
> > Should we just define a subset of printf which is common between
> > iostream and support that or graft a whole lot which is isn't?
> > Ie. truncation of strings is in printf but not iostream,
> > padding with 0 and show base are in iostream but do not interact
> > like printf. (00000x1 rather than 0x00001)
> > Is it acceptable to just make close to printf with well
> > documented differences or is strong compatiblity the best option?
> If it was up to me, I would opt for strong compatibility. I don't think of
> this as an extension to ostream, but rather a suitable implementation of
> printf-style formatting to use in C++. Working well with ostream and string
> seems like a requirement. Using ostream as implementation machinery does
> not.

Okay, if strong compatiblity is best then that should be the direction
we should go. I still don't know which code base is the best
mechanism to achieve that. I think though that I can make the
printf compatiblity even stronger by trying to factor it with
a to_string form. It might give us a smaller code base with the
ablity to do

  cout << format("%c",65);
and get "A".

by calling

  string to_string(65, "%c")

which should return "A".

I am still not sure how you can pull that off and still support
group or manipulators. It would seem to interfer.

> Using ostream to efficiently implement this with a minimum amount of code
> was your idea, and I think it's a pretty good one. But it might get in the
> way of doing a good job at printf compatibility.

Yeah, but it is still worth a try to use as much mechanics as possible.
Small code bases to pull of tasks like this would seem to be


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