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tc39_proposal_object_map #tc39_study
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Jxck
October 09, 2019
Technology
0
630
tc39_proposal_object_map #tc39_study
https://github.com/tc39/proposal-object-map/
#tc39_study
Jxck
October 09, 2019
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Transcript
tc39/proposal-object-map #tc39_study #tc39_study 2019/10/9 Jxck
2 Object.map したい Object.map(([k,v]) => { // snip... }) でも
Object は Iterable じゃないし このままやると slippey slope ...
3 Iterator 側でやろう Iterator.from(obj) .map(([key, value]) => [do(key), do(value)]) .toObject(([key])
=> key, ([, value]) => value); Iterator.from で @@iterator のない Object を許容 反対が多かったら Object.iterate(obj) にする
• Object.entries().map() |> Object.fromEntries じゃだめ? ◦ entries() は Array 生成でコピーが発生するのはわかる
◦ でも toObject は完全に見た目のため (left to right) • Map 使え ◦ JSON.Stringify できないしなぁ ◦ いう気持ちはわかる 4
5 気持ちはわかる....