d的自动柯里化

自动柯里化

​

​f(a,b,c)​

​​按​

​f(a)(b)(c)​

​调用.

template autocurry(alias what) {
    import std.traits;
    static if(Parameters!what.length)
        auto autocurry(Parameters!what[0] arg) {
            alias Remainder = Parameters!what[1 .. $];
            auto dg = delegate(Remainder args) {
                return what(arg, args);
            };

            static if(Remainder.length > 1)
                return &autocurry!dg;
            else
                return dg;
        }
    else
        alias autocurry = what;
}

int foo(int a, string b, float c) {
    import std.stdio; writeln(a, " ", b, " ", c);
    return 42;
}

string test() {
    import std.stdio; writeln("调用测试");
    return "无参";
}

void main() {
    import std.stdio;
    alias lol = autocurry!foo;
    writeln(lol(30)("lol")(5.3));

    auto partial = lol(20);
    partial("wtf")(10.5);

    alias t = autocurry!test;
    writeln(t());
}      

​

​想法​

​​很简单:如果有,根据​

​剩余​

​​参数生成​

​辅助​

​​函数,按​

​闭包​

​​返回​

​辅助​

​​函数​

​地址​

​​,否则,只返回调用​

​收集​

​​参数的​

​闭包​

​​.递归处理​

​多参​

​​,而外部​

​静如​

​​仅返回​

​原始​

​​函数来处理​

​无参​

​.

alias lol = autocurry!foo;
//lol为占位符,      

int foo(int a, string b, float c) {
  import std.stdio;
  writeln(a, " ", b, " ", c);
  return 42;
}

 alias foo = autocurry!foo;
//用原foo重载自动柯里foo
//使用
void main() {
    foo(30)("lol")(5.3); // 柯里版
    foo(40, "cool", 103.4); // 原版
}