Re: is this code valid?
On Jun 4, 5:57 pm, "jason.cipri...@gmail.com"
<jason.cipri...@gmail.com> wrote:
On Jun 4, 5:16 am, James Kanze <james.ka...@gmail.com> wrote:
This sort of thing is why good programmers eschew printf and
company.
Do you happen to know if C++0x is introducing a convenient ostream
interface that makes things like:
printf("%+9.4f %8.3f\n", value1, value2);
Slightly easier to deal with than:
cout << showpos << fixed << setw(9) << setprecision(4) << value1 <<
noshowpos << setw(8) << setprecision(3) << value2 << endl;
Who writes things like that? Normally you'd write something
like:
cout << semantic1 << value1
<< ' ' << semantic2 << value2 << endl ;
Rather than specifying the formatting in each output statement,
you'd define application specific formatting for the specific
semantics of the values in your application, and use them. (For
what it's worth, I think that setw() is the only standard
manipulator I've ever used.)
Do you also happen to know if C++0x is introducing an
iostreams interface with informative error returns, e.g an
equivalent of:
string errmsg;
if (fprintf(...) < 0)
errmsg = strerror(errno); // <-- ?
I find iostreams has little to no value over stdio when you
are only dealing with built-in scalar types.
If you put no value on avoiding errors and undefined behavior,
nor on using logical mark-up, rather than low level physical
formatting primitives, nor on being able to output to more or
less anything, inserting filters, etc., without changing the
code doing the outputting, then they don't add much value, no.
I consider all three of those points important for good software
engineering, however.
Of course it's convenient to define new ostream << operators
for complex types; but for this kind of stuff iostreams is
incredibly cumbersome...
I find it less cumbersome than fprintf. And far less error
prone.
--
James Kanze (GABI Software) email:james.kanze@gmail.com
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