D言語でカリー化実装してみた

curry.d

import std.stdio;

template curry(alias func){
  import std.algorithm, std.conv, std.range, std.traits;
  alias argsintuple = ParameterTypeTuple!func;

  immutable lambdaStr = (lamArgs =>
    (temp){
      foreach(i, e; argsintuple)
        temp ~= "(" ~ e.stringof ~ " " ~ lamArgs[i] ~ ") => ";

      return temp ~ "func(" ~ lamArgs.join(", ") ~ ")";
    }("")
  )(argsintuple.length.iota.map!(i => "arg" ~ i.to!string));

  enum curry = mixin(lambdaStr);
}

int f(int x, int y, int z){
  return x * y * z;
}

void main(){
  auto fc = curry!f;
  assert(fc(1)(2)(3) == f(1, 2, 3);
}

どや！

template curry(alias func){
  import std.algorithm, std.conv, std.range, std.traits;
  alias argsTuple = ParameterTypeTuple!func;

  immutable lambdaStr = (lamArgs =>
    (temp){
      foreach(i, e; argsTuple){
        temp ~= "(" ~ e.stringof ~ " " ~ lamArgs[i] ~ ") => ";
      }
      return temp ~ "func(" ~ lamArgs.join(", ") ~ ")";
    }("")
  )(argsTuple.length.iota.map!(i => "arg" ~ i.to!string));

  // pragma(msg, lambdaStr);
  enum curry = mixin(lambdaStr);
}

int f(int x, int y, int z){
  return x * y * z;
}

void main(){
  import std.stdio;
  typeof(curry!f).stringof.writeln;
  assert(curry!f(2)(3)(5) == f(2, 3, 5));
}

Thx!