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Colin Wills · Guest

I am trying to get the compiler to specialise a general purpose lookup
object based on maps to use arrays when a reasonable int range is the
lookup parameter. (This is a simplified extract of what I'm trying to
do.) I want the int range and decision to use arrays to be worked out
at compile time but gcc doesn't like the ERROR commented row below.
What's the right syntax for this partial specialisation with a template
template parameter?

#include <iostream>
#include <map>
#include <string>

using namespace std;

template <typename RT, typename LT>
class Table
{
map<LT,RT> m_data;
public:
void add(LT param, RT value) {m_data[param] = value;}
RT& operator[] (LT param) {return m_data[param];}
};

template <int S>
class IntRange
{
enum {size = S};
};

template <typename RT>
class Table<RT, template
// ERROR: syntax error before `template'
{
RT m_data[IntRange::size];
public:
void add(int param, RT value) {m_data[param] = value;}
RT operator[] (int param) {return m_data[param];}
};

int main()
{
Table<double,string> t1;
t1.add(string("fred"),42.5);
cout << "t1[fred]=" << t1[string("fred")] << endl;

// Table t2;
// t2.add(4,3.14);
// cout << "t2[4]=" << t2[4] << endl;
}

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Thomas Maeder · Guest

"Colin Wills" <colin (AT) nonhtmlmail (DOT) org> writes:

Maxim Yegorushkin · Guest

Colin Wills <colin (AT) nonhtmlmail (DOT) org> wrote: