(xs2, f)
| 955 | return keys; |
| 956 | }; |
| 957 | function map(xs2, f) { |
| 958 | if (xs2.map) { |
| 959 | return xs2.map(f); |
| 960 | } |
| 961 | var res = []; |
| 962 | for (var i = 0; i < xs2.length; i++) { |
| 963 | res.push(f(xs2[i], i)); |
| 964 | } |
| 965 | return res; |
| 966 | } |
| 967 | function reduce(xs2, f, acc) { |
| 968 | if (xs2.reduce) { |
| 969 | return xs2.reduce(f, acc); |