expected init-declarator before "type" in templated typedef

Question

I am trying to complie the code below.

template <class T1, class T2>
class class1
{
typedef T1 Type1;
typedef T2 Type2;
//void class1Method();
};


template <class T1>
class class2
{
typedef T1 Type1;
void class2Method();
};

template <class T1>
void class2<T1>::class2Method()
{
 typedef class1<T1,T1>::Type1 Type3;
}

However, I get the error shown below.

g++ -g -c class12.h -o class12.o
class12.h: In member function `void class2<T1>::class2Method()':
class12.h:20: error: expected init-declarator before "Type3"
class12.h:20: error: expected `,' or `;' before "Type3"
make: *** [class12.o] Error 1

What am I doing wrong?

Can somebody please let me know?

Thanks

score 4 · Accepted Answer · answered Mar 06 '13 at 19:08

4

You need a typename

typedef typename class1<T1,T1>::Type1 Type3;

Furthermore, you need to make the typedef in class1 public.

template <class T1, class T2>
class class1
{
 public:
  typedef T1 Type1;
  typedef T2 Type2;
};

answered Mar 06 '13 at 19:08

juanchopanza

210,243
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d'oh - beat me to it. – Nik Bougalis Mar 06 '13 at 19:09
@juanchopanza do you mean I can define a type within a function scope? – geraldCelente Mar 06 '13 at 20:09
1

@geraldCelente Yes, you can. – juanchopanza Mar 06 '13 at 20:11

score 1 · Answer 2 · answered Mar 06 '13 at 19:08

1

Try using typename:

typedef typename class1<T1,T1>::Type1 Type3;

answered Mar 06 '13 at 19:08

Nik Bougalis

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expected init-declarator before "type" in templated typedef

2 Answers2