Function.h

Heap allocation free version of C++11 std::function.

Function.h stores the closure in an internal buffer instead of heap allocated memory. This is useful for low latency agent and thread pool systems. Please note that the captured values can perfom allocations, for example std::string.

Benchmark

Function.h is quite a lot faster than std::function to construct. Invocation overhead is the same for both.

Compiled with gcc -O3 -fno-devirtualize (gcc 5.2).

construction overhead
  std::function: 42ns/op
  Function:      4ns/op
  
invokation overhead:
  std::function: 2ns/op
  Function:      2ns/op
  virtual:       2ns/op