ruby-dev

こんにちは、なかむら(う)です。

In message "[ruby-dev:38495] Re: [Feature:trunk] enhancement of Array#drop"
    on May.19,2009 16:20:07, <matz@ruby-lang.org> wrote:
| |Rubyでスクリプトを書いていて、配列から、ある条件に合致する先
| |頭の要素のみを削除する、という処理を書きたい場面に出会ったこ
| |とが何度かあります。
| |
| |無条件で先頭の要素を削除するメソッドとしてはshiftまたはdrop(1)
| |があり、また、条件に合致した全ての要素を削除するメソッドとし
| |てはdeleteがありますが、ある条件に合致する先頭の要素のみを削
| |除しようとすると、意外と複雑な記述になってしまいます。
| |
| |... という話をIRCでしてみたところ、なかださんに「dropにブロッ
| |ク引数を追加するのはどうか」と言われました。
| 
| drop_whileとは違うのですね。

私が勘違いしてなければ、drop_whileは「ある条件に合致する要素
より前の要素を全て削除する」ですから、私が欲しい物とは違うよ
うです。
戻り値や対象未発見時の例外の有無などを無視すれば、私が欲しい
物は ary.delete_at(ary.index(elem)) と書けます。


それでは。
-- 
U.Nakamura <usa@garbagecollect.jp>

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[ruby-dev:38500] Re: [Feature:trunk] enhancement of Array#drop

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[#38496] [Bug #1489] Netbeansからruby-debug-ideを利用した際　Segmentation faultが発生。 — Kiyokazu Hayashi <redmine@...>

[#38498] [Bug #1491] 「attr_reader :○○」と「def ○○ ; @○○ ; end」で動作が異なる — 慎一江口 <redmine@...>