🚀 go-pugleaf

In <1992Sep15.054226.4126@cc.tut.fi> jk87377@cc.tut.fi (Juhana Kouhia) writes:

>Hi,

>I'm very new in C++ world; I have not done any programs so far;
>and I'm currently reading C++ Primer books on chapter 3   :-)

>Instead of making exponential operator; I would like to get
>a new basic operation which allows programmer to define new
>operations like 'a ** b'; that is, the '**' is defined.
>('a pow b' is also good.)

*****>	The short answer is that it's a _real_ pain.  The somewhat
	longer answer is that making new operators means that you have
	to also establish the precedence and associativity of the new
	operator relative to all the other operators *AND* any other
	operators created by other people.  Every time an operator is
	added, the hierarchy would have to be readjusted.

	For new operators, the precedence and associativity may seem
	arbitary at the time of creation, but it may later be realised,
	after experience, that it could have been done better...of
	course it's too late to change it now because code would break.

	Also, if you were to use library X and library Y, each could use
	the same operator for different reasons, and the two operators
	were developed without regard to the others precedence and
	associativity; how would the compiler resolve this?  (I'm not
	looking for people to show how smart they are here by telling me
	how a compiler could resolve this...the point is that even if
	the compiler could do it, most _people_ would have a tough time
	looking at the code.)

	It's more trouble than its worth.  The _point_ of operator
	overloading is to give an operator a _natural_ extension to
	another type.  People shouldn't sit around trying to figure out
	how to force an operator (square peg) to be used for a new type
	(round hole).  If the operator's use in a new context isn't
	intuitively obvious, forget it and use function-notation.
-- 
	- Paul J. Lucas				University of Illinois	
	  AT&T Bell Laboratories		at Urbana-Champaign
	  Naperville, IL			pjl@cs.uiuc.edu