@{
    append(s, e) {
      s[length(s)] = e;
    }

    map(f, seq, g) {
      out = {};
      if (g) {
        for (i in seq) {
          e = seq[i];
          if (g(e)) { e = f(e); }
          append(out, e);
        }
      } else {
        for (i in seq) {
          append(out, f(seq[i]));
        }
      }
      out;
    }

    select(f, s) {
      out = {};
      for (i in s) {
        e = s[i];
        if (f(e)) { append(out, e); }
      }
      out;
    }

    reject(f, s) {
      out = {};
      for (i in s) {
        e = s[i];
        if (!f(e)) { append(out, e); }
      }
      out;
    }
    
    toChar(foo) {
        "\"type :"+foo+"\"";
    }
    p2(foo) {
        foo * foo;
    }
    c = ["earth", "sky", "water"];
    isSky(x) { x == "sky" }
    c = reject(isSky, c);
    
}

@{print(map(p2, [100, 2, 3]));}

@{print(map(toChar, c));}

enum foo { A, B, C };
enum oof { A, B, C };

@{
  isEnum(x)   { x.__proto__ == C_enum }
  notToken(x) { x.__proto__ != Token  }
  to_C_string(x)  {{ __proto__: C_string, value: "\"" + string(x.name.identifier) + "\"" }} 
  // to_C_string(properties.enums.foo.enumList[?].name.identifier);

  a = map(to_C_string, select(isEnum, properties.enums.foo.enumList));
  b = map(to_C_string, properties.enums.foo.enumList, notToken);
  c = map(to_C_string, properties.enums.foo.enumList, isEnum);
}

char *a[] = { @(a) };

char *b[] = { @(b) };

char *c[] = { @(c) };