Re: question on map< list<T>::iterator, int>

On 2008-05-03 08:48:01 -0400, "subramanian100in@[EMAIL PROTECTED]
 India" 
<subramanian100in@[EMAIL PROTECTED]
> said:

> 
> This program compiles fine with the command
> g++ -std=c++98 -pedantic -Wall -Wextra  x.cpp
> 
> However if I remove the comment, I get compilation error because
> operator '<' is not defined for list<T>::iterator. Why doesn't the
> compiler give this error for
> 'map<list<int>::iterator, int> m;' itself. That is, in this first
> statement inside main() itself, the compiler can know that the less-
> than operator cannot be defined for the key type. So, why does the
> compiler wait for an element to be pushed on to the map to flag the
> error ?
> 

The compiler doesn't compile template code that isn't used, so it 
doesn't notice the missing operator< until it's used.

-- 
  Pete
Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The 
Standard C++ Library Extensions: a Tutorial and Reference 
(www.petebecker.com/tr1book)