ruby-dev

  藤本です。

From: OZAWA Sakuro <crouton@pop13.odn.ne.jp>
Subject: [ruby-dev:3431] Re: grand renaming
Date: Wed, 29 Jul 1998 22:06:12 +0900

> さくです．ISP変えました。
> 
> 脱線します。
> 
> In article <19980729190252H.hisa@cream.imasy.or.jp>,
>     藤本尚邦 / Hisakuni FUJIMOTO <hisa@imasy.or.jp> writes:
> 
> >   TRUEも値が違うんですが、
> > Cの真偽値のしくみから考えて実際には問題なさそうです。
> 
> 先日、会社の所属プロジェクトの人のソースを見たんですが、
> 	if (result == TRUE) ... 
> みたいなコードがあって、ちょっと不安になりました。

  「問題なさそう」と書いたもののちょっと不安だったんですが、そう言われ
てみると、NIL同様にTRUEもちょっと危険なのかなという気がしてきました。

> 一般に、FALSEは0だと思っていいけど、TRUEは0ではない、という
> 以外に値の保証がないので、等号で比較してはいけないと教わったので。

  これはRubyを離れた話しですよね。だとすると、TRUEがどのように定義され
ているかによるんじゃないでしょうか？もし

#define FALSE 0
#define TRUE (!FALSE)

みたいな定義だったら

> 	if (result == TRUE) ... 

と書かれていても安全ですよね。

=============================================================
 藤本尚邦  FUJIMOTO Hisakuni                hisa@imasy.or.jp
=============================================================

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[#3156] Re: bignum of ruby11b9_28 — 助田 雅紀 <masaki.suketa@...>

[#3157] Re: thread and STDIN.gets — 助田 雅紀 <masaki.suketa@...>

[#3167] Re: bignum of ruby11b9_28 — 助田 雅紀 <masaki.suketa@...>

[#3171] Re: bignum of ruby11b9_28 — 助田 雅紀 <masaki.suketa@...>

[#3173] Re: bignum of ruby11b9_28 — 助田 雅紀 <masaki.suketa@...>

[#3175] Re: bignum of ruby11b9_28 — 助田 雅紀 <masaki.suketa@...>

[#3176] Re: Enumerable#reverse ([ruby-list:8579]) — "YANAGAWA Kazuhisa" <kjana@...>

[#3177] Re: experimental release 1.1b9_28 — "YANAGAWA Kazuhisa" <kjana@...>

[#3180] Re: Enumerable#reverse ([ruby-list:8579]) — "MAEDA Shugo" <shugo@...>

[#3181] Re: [REQ] caller binding — "MAEDA Shugo" <shugo@...>

[#3183] Re: experimental release 1.1b9_28 — "YANAGAWA Kazuhisa" <kjana@...>

[#3184] Re: once function — "MAEDA Shugo" <shugo@...>

[#3186] Re: once function — "MAEDA Shugo" <shugo@...>

[#3192] TkText — NAGAI Hidetoshi <nagai@...>

[#3210] experimental release 1.1b9_29 — matz@... (Yukihiro Matsumoto)

[#3215] [BUG] a ||= 1 and a &&= 1 — keiju@... (Keiju ISHITSUKA)

[#3218] [BUG] / あ a/i =~ " あ a" — WATANABE Hirofumi <watanabe@...>

[#3225] Ruby/Tk unofficial patch — NAGAI Hidetoshi <nagai@...>

[#3229] [BUG] ruby-mode.el — keiju@... (Keiju ISHITSUKA)

[#3234] sample of TkFont class — NAGAI Hidetoshi <nagai@...>

[#3235] [BUG] IO#readlines and Thread — keiju@... (Keiju ISHITSUKA)

[#3237] [BUG] Thread.abort_on_exception — keiju@... (Keiju ISHITSUKA)

[#3238] [BUG] Thread.value — keiju@... (Keiju ISHITSUKA)

[#3239] [REQ] abort — keiju@... (Keiju ISHITSUKA)

[#3249] experimental release 1.1b9_30 — matz@... (Yukihiro Matsumoto)

[#3261] [BUG] format(nil, arg) — gotoken@... (GOTO Kentaro)

[#3263] ary_length — ttate@...

[#3268] pstore.rb — keiju@... (Keiju ISHITSUKA)

[#3283] [Request] GC methods — ttate@...

[#3285] TkWinfo .id — Kazunori NISHI <kazunori@...>

[#3292] exprimental release 1.1b9_31 (hopefully final) — matz@... (Yukihiro Matsumoto)

[#3296] regexp bug? on BeOS — "MAEDA Shugo" <shugo@...>

[#3298] safe level — ttate@...

[#3311] REQUEST id2name — Shin-ichro Hara <sinara@...>

[#3315] Re: regexp bug? on BeOS — "MAEDA Shugo" <shugo@...>

[#3316] Re: regexp bug? on BeOS — "MAEDA Shugo" <shugo@...>

[#3335] format — Inaba Hiroto <inaba@...>

[#3336] Kanji treatment in String#inspect & mbctab definition — Inaba Hiroto <inaba@...>

[#3343] [Bug?] attr_??? — ttate@...

[#3344] tk.rb patch (for ruby-1.1c0) — ttate@...

[#3353] tk.rb and tkfont.rb — Takahiro Maebashi <maebashi@...>

[#3373] [BUG] attr — WATANABE Tetsuya <tetsu@...>

[#3386] DATA — WATANABE Tetsuya <tetsu@...>

[#3393] tk.rb patch — NAGAI Hidetoshi <nagai@...>

[#3410] dialogue — Tadayoshi Funaba <tadf@...>

[#3411] Array.new(1<<30) — Tadayoshi Funaba <tadf@...>

[#3412] tk.rb — Tadayoshi Funaba <tadf@...>

[#3424] [BUG] String#[pos, len]= val — keiju@... (Keiju ISHITSUKA)

[#3427] grand renaming — matz@... (Yukihiro Matsumoto)

[#3437] [BUG?] scan — WATANABE Tetsuya <tetsu@...>

[ruby-dev:3432] Re: grand renaming

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In This Thread

[#3156] Re: bignum of ruby11b9_28 — 助田　雅紀 <masaki.suketa@...>

[#3157] Re: thread and STDIN.gets — 助田　雅紀 <masaki.suketa@...>

[#3167] Re: bignum of ruby11b9_28 — 助田　雅紀 <masaki.suketa@...>

[#3171] Re: bignum of ruby11b9_28 — 助田　雅紀 <masaki.suketa@...>

[#3173] Re: bignum of ruby11b9_28 — 助田　雅紀 <masaki.suketa@...>

[#3175] Re: bignum of ruby11b9_28 — 助田　雅紀 <masaki.suketa@...>