Implementing Matlab's colon : operator in C++ expression templates class -

i'm implementing c++ expression templates library. have set proper submatrixexpr class collect elements within matrix, enabling syntax like

b = submatrix(a,1,3,2,10); 

which equivalent matlab's

b = a(1:3,2:10); 

of course, matlab's syntax more confortable mine. question is

is there possibility set matlab's colon : operator in c++?

thank in advance.

short answer: no. colon not valid c++ operator, cannot overloaded. , if could, still not possible achiev need easily, because surely have precedence on comma operator, make expression in lines of a((1:3),(2:10)), , allowed overload operators if 1 of operands user defined type (which not case here).

so other operator in place, not looks this.

what can do: overload operator() matrix class, sensible arguments. enable write b = a(1,3,2,10);, if define operator()(int,int, int, int);

my preferred solution operator() taking either 2 initializer_lists in c++11 or 2 std::array<int,2>. former have check list contains 2 elements, latter need awkward double brace initialization - might disappear in c++14 or later (n3526, afaik it's not in cd c++14). third possibility of course named class call, presenting range:

class matrix {   /* ... */ public:   matrix operator()(std::initializer_list<int> range1, std::initializer_list<int> range2);   //or:   matrix operator()(std::array<int,2> range1, std::array<int,2> range2);   //or:   matrix operator()(range range1, range range2);  };  int main() {   matrix a;   /* ... */   matrix b = a({1,3}, {2,10}); //beware of a({1,3,2,4,5}, {0}) !   //or:   matrix b = a({{1,3}}, {{2,10}}); //uhgs...   //or:   matrix b = a(range(1,3), range(2,10)); //more verbose, more understandable }