Re: Iterator in a template

red floyd <>
Wed, 18 Jan 2012 22:36:37 -0800
On 1/18/2012 8:49 PM, Pierre Abbat wrote:

I've used map iterators before; this is my first time making a template.
hvec (hexagonal vector) is an integral (in the mathematical sense) type
representing a point in a hexagonal lattice. A harray is an array
subscripted by an hvec. Currently I use only bytes as the elements, but I
will need to store larger things in harrays, so I made it a template. I
wrote this code to clear all elements in the harray:

template<typename T> class harray
{map<hvec,T *> index;
  T& operator[](hvec i);
  void clear();

template<typename T> T& harray<T>::operator[](hvec i)
{hvec q,r;
  if (!index[q])
  return index[q][r.pageinx()];

template<typename T> void harray<T>::clear()
{map<hvec,T *>::iterator i; // line 78
  for (i=index.start();i!=index.end();i++)

When I try to compile it, I get this error:

In file included from /home/phma/hexcode/hexcode.cpp:5:
/home/phma/hexcode/hvec.h: In member function 'void harray<T>::clear()':
/home/phma/hexcode/hvec.h:78: error: expected ';' before 'i'
/home/phma/hexcode/hvec.h:79: error: 'i' was not declared in this scope

How can I fix it?

hmap<>::iterator is a dependent type. use
"typename map<hvec, T*>::iterator"

I believe this is in the FAQ

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