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gino · Guest

Hi everybody,

while playing around with a map-based class, I stumbled into a strange
gcc behaviour. The code goes like this:

template<typename K, class D>
class Directory
{
typedef std::map<K, D> MapType;
typedef MapType::value_type Pair; // won't compile

public:
typedef MapType::iterator MapIter; // won't compile

Directory() {}
~Directory() {}

void add(D d, K k) { map_.insert(Pair(k, d)); }
D get(K k) { return map_[k]; }
MapIter begin() { return map_.begin(); }
MapIter end() { return map_.end(); }

private:
MapType map_;

};

When trying to compile the above with gcc 3.4.3 (20050110), I get these
errors:

directory.h:17: error: type `std::map<K, D, std::less<_Key>,
std::allocator<std::pair >' is not derived from type
`Directory<K, D>'
[...]
directory.h:20: error: type `std::map<K, D, std::less<_Key>,
std::allocator<std::pair >' is not derived from type
`Directory<K, D>'
[...]

If I substitute the template with explicit types (i.e. I manually
change D and K with real types), the code compiles (and works) cleanly.
Even stranger, the above code compiles cleanly with Visual C++.

Any ideas or suggestions?

Thanks and regards,
Gianluca

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Falk Tannhäuser · Guest

gino wrote:

Marco Manfredini · Guest

gino wrote:

Thomas Maeder · Guest

"gino" <insol (AT) tiscalinet (DOT) it> writes:

Ben Hutchings · Guest

gino wrote:

kanze@gabi-soft.fr · Guest

Falk Tannhäuser wrote: