From: Tanaka Akira <akr@...17n.org>
Date: 2002-06-24T16:25:47+09:00
Subject: [ruby-dev:17564] Re: blocks and local variables

In article <1024899653.239780.6639.nullmailer@picachu.netlab.jp>,
  matz@ruby-lang.org (Yukihiro Matsumoto) writes:

> $B$?$@!"(Bx = foo(x) $B$r5v$9$H:#EY$O!V(Bx $B$N%9%3!<%W$O$J$K!)!W$H$$(B
> $B$&5?Ld$r8F$V$3$H$K$J$k$H;W$$$^$9!#$H$$$&$3$H$G!"$$$C$=(B
> 
>   {<> ..>
> 
> $B$NCf$G$O(B($B@k8@$7$J$$8B$j(B)$B30$N%m!<%+%kJQ?t$O8+$($J$$$H$$$&3d$j(B
> $B@Z$j$,J,$+$j$d$9$5$NAmOB$,:GBg$G$O$J$$$+$H9M$($k$h$&$K$J$C$F(B
> $B$^$9!#(B

$B$U$`!#8=:_$b(B x = foo(x) $B$O2DG=$G!"%9%3!<%W$H$7$F$ON>J}$N(B x $B$OF1$8$G!"(B
$B1&JU$G;2>H$7$?;~E@$G$O(B nil $B$G$"$j!"$=$N$"$H$K:8JU$N(B x $B$KBeF~$9$k$3$H$K(B
$B$J$k$o$1$G$9!#(B

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$B$i$G$9$,!"$3$N$?$a$K!"(B

  x = foo(x)

$B$H$7$F$J$<$+(B nil $B$,0z?t$H$7$FEO$5$l$k$H$$$&$3$H0J30$K!"(B

  if false
    x = 1
  else
    p x
  end

$B$H$G$-$F$7$^$&$H$+!"(B

  p x if (x = ...).pred?

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$B$JA*Br$@$H$O;W$($^$;$s!#(B

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$B7h$^$k@)8f$NN.$l$N=g$G(B scan $B$9$k$H$$$$$N$G$O$J$$$+$H;W$C$F$$$?$j$7$^$9!#(B
(Java $B$N(B definitive assignment $B$_$?$$$K!#(B)

$B$^$?!"%Q%i%a!<%?$N$H$3$m$G@k8@$5$;$F30$r8+$k$H$$$&$N$O(B Python 2.0 $B$^$G(B
$B$,$^$5$K$=$s$J$+$s$8$G$7$?!#$,!"$3$l$O;H$$$K$/$/$F(B Python 2.1 $B$G$D$$$K(B
$BJQ$o$C$?$o$1$G$9!#(B
http://www.python.org/peps/pep-0227.html
http://www.amk.ca/python/2.1/index.html#SECTION000300000000000000000

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$B;W$C$F$$$^$9!#(B
-- 
[$BEDCf(B $BE/(B][$B$?$J$+(B $B$"$-$i(B][Tanaka Akira]
$B!V$U$($m(B! $B$o$+$a$A$c$s:n@o$G$9$(C"=$B!W(B(Little Worker, $B7KM7@84](B)