[mule-ja:42] nocopy argument of code_convert_string

[Ikumi Keita]

  emacs 24.5 $B$N(B coding.c $B$N(B code_convert_string 
$B$N;O$a$NJ}$N0J2<$NItJ,$G(B
$B$9$,!"(Breturn $B$N9T$G(B nocopy 
$B$,??$N;~$N=hM}$H56$N;~$N=hM}$,5U$K$J$C$F$$$J(B
$B$$$G$7$g$&$+!#(B
----------------------------------------------------------------------
  if (NILP (coding_system))
    {
      if (! norecord)
        Vlast_coding_system_used = Qno_conversion;
      if (NILP (dst_object))
        return (nocopy ? Fcopy_sequence (string) : string);
    }
----------------------------------------------------------------------
  $B<!$N$h$&$K%F%9%H$7$F$_$^$7$?$,!"$d$C$Q$j5U$K$J$C$F$$$k$h$&$K8+$($^$9!#(B
(let* ((s1 "abc")
       (s2 (encode-coding-string s1 nil nil))) ; nocopy $B$O56(B
  (eq s1 s2))
        => t ; $BF~NO$N(B s1 $B$,$=$N$^$^JV$C$F$$$k(B

(let* ((s1 "abc")
       (s2 (encode-coding-string s1 nil t))) ; nocopy $B$O??(B
  (eq s1 s2))
        => nil ; s1 $B$N%3%T!<$,JV$C$F$$$k(B

  $B$=$l$+$i!"$3$l$K4XO"$7$?OC$G$9$,!"(Bcode_convert_string $B$G(B nocopy 
$B$r;H$C(B
$B$F$k$N$C$F>address@hidden&$3$H$O!"(B
{de,en}code-coding-string $B$N<BBN$,(B
  code_convert_string (string, coding_system, buffer,
                              0, ! NILP (nocopy), 0);
$B$d(B
  code_convert_string (string, coding_system, buffer,
                              1, ! NILP (nocopy), 0);
$B$G$"$k$3$H$b9M$($k$H!"(B{de,en}code-coding-string $B$G(B nocopy 
$B0z?t$N;XDj$K0U(B
$BL#$,$"$k$N$O!"(Bcoding-system $B0z?t$r(B nil $B$K$7$F(B
(decode-coding-system str nil t)
$B$_$?$$$K;H$&address@hidden(B
  $B$3$l$i$N(B doc string $B$N(B

Optional third arg NOCOPY non-nil means it is OK to return STRING
itself if the decoding operation is trivial.

$B$+$i$O!"!VJQ49$r$+$1$h$&$H$7$?$1$l$I$b7k6I$I$NJ8;z$bJQ49$5$l$J$+$C$?!W>l(B
$B9g$O!"(BNOCOPY $B$,address@hidden(B STRING 
$B$,$=$N$^$^JV$5$l$k$N$+$H$F$C$-$j;W$C$F$$$^(B
$B$7$?$,!"$=$&$G$O$J$/$F!"address@hidden&!V(Btrivial$B!W$NDj5A$H$O!V(BCODING-SYTEM
 $B0z(B
$B?t$,(B nil $B$G$"$k$3$H!W$H$$$&address@hidden&$+!#(B

                                                $B0f5b(B address@hidden(B