Experimental Physics and
Industrial Control System

Kay-Uwe Kasemir <[email protected]> · Mon, 18 Jul 2005 10:31:02 -0400

Hi:

Jeff wrote:

2) I'm not terribly fond of interfaces that hand off handles to

internal

data. I'm not enamored, for example, with "std::string::c_str()" and
"EpicsString::expose".

In principle, I agree that c_str violates everything you learn
about using interfaces and hiding the internal data.

In fully OO languages like Java where a string constant "blah" is
interchangeable with a String class and all library functions understand
this, we'd be fine.

In reality, however, I'm afraid that many C and C++ APIs still require
text as (const char *), so whatever String class we use needs to
convert to/from char * as efficiently as possible,
and c_str does that for 'reading' the String.
So just like std::string and MFC::CString and probably most of the other
C++ string classes, I doubt you can avoid char *.

-Kay

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System