Experimental Physics and
Industrial Control System

Chris Larrieu <[email protected]> · Fri, 08 Dec 2000 17:15:37 -0500

Andrew Johnson wrote:
> 
> places).  In the above case, if no suitable comparison operator (cit !=
> it) exists then the compiler will automatically convert the RHS to cit and
> use (cit != cit).
> 

  Nope.  That's my whole point.  While the standard does allow for 
explicitly converting an iterator to a const_iterator, there is no 
special rule for implicit conversion, just the regular C++ rules
for resolving overloaded template functions.  See section 14.8.3.

> My current list implementation allows either order in comparisons, but I
> could take out the (it == cit) operations if you really think this is

  If your operators are friend functions, the only way this will compile 
with HP's aCC is by explicitly casting; order is of no consequence:

        (cit == (const_iterator)it), or ((const_iterator)it == cit)

  On the other hand, if you define these operators as member
functions of iterator and const_iterator, there shouldn't be any 
problem with template deduction.

Chris
-- 
Christopher A. Larrieu
Computer Scientist, Acc. Controls Group
Thomas Jefferson National Accelerator Facility

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System