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A C++17 memoization library

memo

Build status

memo is a small C++17 library designed to allow for easy memoization of functions.

Example

#include <memo.hpp>

// Use a regular function:
int foo(int a, int b) {
  return a + b;
}
auto memo_foo = memoize(foo);
int x = memo_foo(1, 2);

// Or a lambda:
auto memo_lambda = memoize([](int a, int b) {
  return a + b;
});
int y = memo_lambda(1, 2);

// Or a polymorphic function object:
struct bar {
  int operator ()(int a, int b);
  float operator ()(float a, float b);
};
auto memo_bar = memoize<int(int, int)>(bar{});

// Or a recursive function:
auto fib = recursive_memoize([](auto &fib, size_t n) -> size_t {
  switch(n) {
  case 0:
    return 0;
  case 1:
    return 1;
  default:
    return fib(n-1) + fib(n-2);
  }
});

// You can also specify the return type of your recursive function if the above
// fails:
auto fib2 = recursive_memoize<size_t>(...);

// Or even the full signature:
auto fib3 = recursive_memoize<size_t(size_t)>(...);

Requirements

This library requires a C++17-compliant compiler. Additionally, to run the tests, you'll need mettle.

License

This library is licensed under the BSD 3-Clause license.