c++ - Efficient dispatch from "name",number to template handler functions

Question

I have an input file that looks like:

op1000,3,free-form,data
op1002,1,other,data,1.0 

I have a number of template functions:

template<int version>
static bool op1000(const char * s) { /* parse free-form data */ }

My current method is:

struct op2func
{
  const char * op;
  const int version;
  bool (*parse)(const char *s);
};

op2func mapping[] =
{
{ "op1000",0,op1000<0> },
{ "op1000",1,op1000<1> },
{ "op1000",2,op1000<2> },
{ "op1000",3,op1000<3> },
{ "op1002",0,op1000<0> },
{ "op1002",1,op1000<1> }
};

This involves a linear search for a matching name and version -- this used to be a binary search, but adding new entries in the right place was too challenging for some developers; along with the overhead of a strcmp() per entry.

There HAS to be a better way to handle this scenario. A C++11 solution is preferred if practical.

Ideally, I'd like something that takes a list of possible operation names and generates a compile-time switch.

question from:https://stackoverflow.com/questions/66067759/efficient-dispatch-from-name-number-to-template-handler-functions

Answer 1

Waitting for answers