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再帰的なtypeof; nullや配列はobject型として判定しない
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| export default deepTypeof; | |
| /** | |
| * 再帰的なtypeof; nullや配列はobject型として判定しない | |
| * @param {*} value 型を調べるデータ | |
| * @returns {string} 型名 | |
| */ | |
| function deepTypeof(value) { | |
| const typename = typeof value; | |
| if (value === null) { | |
| // typeof null === "object" なので、nullは先にチェック | |
| return "null"; | |
| } | |
| if (Array.isArray(value)) { | |
| // typeof [] === "object" | |
| return _array(value); | |
| } | |
| if (typename === "object") { | |
| return _object(value); | |
| } | |
| return typename; | |
| } | |
| /** | |
| * 配列のtypeof | |
| * @package | |
| * @param {Array<*>} value 型を調べるデータ（配列型） | |
| * @returns {string} 型名 | |
| */ | |
| function _array(value) { | |
| const types = []; | |
| for (const v of value) { | |
| // 各要素を再帰処理 | |
| types.push(deepTypeof(v)); | |
| } | |
| return `[${types.join(",")}]`; | |
| } | |
| /** | |
| * オブジェクトのtypeof | |
| * @package | |
| * @param {Object<string, *>} value 型を調べるデータ（オブジェクト型） | |
| * @returns {string} 型名 | |
| */ | |
| function _object(value) { | |
| const types = []; | |
| for (const [k, v] of Object.entries(value)) { | |
| // 各要素を再帰処理; キーはエスケープしておく | |
| types.push(`${JSON.stringify(k)}:${deepTypeof(v)}`); | |
| } | |
| return `{${types.join(",")}}`; | |
| } |
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| import deepTypeof from "deep-typeof"; | |
| import assert from "assert"; | |
| assert.strictEqual(deepTypeof(null), 'null'); | |
| assert.strictEqual(deepTypeof(123), 'number'); | |
| assert.strictEqual(deepTypeof('abc'), 'string'); | |
| assert.strictEqual(deepTypeof(true), 'boolean'); | |
| assert.strictEqual(deepTypeof([null, 123, 'abc', true]), '[null,number,string,boolean]'); | |
| assert.strictEqual(deepTypeof({key: 123}), '{"key":number}'); | |
| assert.strictEqual(deepTypeof({array: [null, 123], object: {key: "abc"}}), '{"array":[null,number],"object":{"key":string}}'); | |
| /* 再帰で死ぬのでこういうことはやらないように | |
| const data = {}; | |
| data.abc = data; | |
| deepTypeof(data); | |
| */ |
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