@comment $OpenXM: OpenXM/src/asir-doc/parts/builtin/structure.texi,v 1.3 2003/11/27 15:56:08 ohara Exp $
\BJP
@node 構造体,,, 組み込み函数
@section 構造体
\E
\BEG
@node Structures,,, Built-in Function
@section Structures
\E

@menu
* newstruct::
* arfreg::
@end menu

\JP @node newstruct,,, 構造体
\EG @node newstruct,,, Structures
@subsection @code{newstruct}
@findex newstruct

@table @t
@item newstruct(@var{name})
\JP :: 構造体名が @var{name}の構造体を生成する. 
\EG :: Creates a new structure object whose name is @var{name}.
@end table

@table @var
@item return
\JP 構造体
\EG structure
@item name
\JP 文字列
\EG string
@end table

@itemize @bullet
@item
\JP 名前が @var{name} である構造体を生成する. 
\EG This function creates an new structure object whose name is @var{name}.
@item
\JP あらかじめ, @var{name} なる構造体が定義されていなければならない. 
\EG A structure named @var{name} should be defined in advance.
@item 
\BJP
構造体の各メンバは演算子 @code{->} により名前でアクセスする.
メンバが構造体の場合, 更に @code{->} による指定を続けることができる. 
\E
\BEG
Each member of a structure is specified by its name using the operator
@code{->}. If the specified member is also an structure, the specification
by @code{->} can be nested.
\E
@end itemize

@example
[0] struct list @{h,t@};    
0
[1] A=newstruct(list);
@{0,0@}
[2] A->t = newstruct(list);
@{0,0@}
[3] A; 
@{0,@{0,0@}@}
[4] A->h = 1;
1
[5] A->t->h = 2;
2
[6] A->t->t = 3;
3
[7] A;
@{1,@{2,3@}@}
@end example

@table @t
\JP @item 参照
\EG @item References
@fref{arfreg},
\JP @fref{構造体定義}
\EG @fref{structure definition}
@end table

\JP @node arfreg,,, 構造体
\EG @node arfreg,,, Structures
@subsection @code{arfreg}
@findex arfreg

@table @t
@item arfreg(@var{name},@var{add},@var{sub},@var{mul},@var{div},@var{pwr},@var{chsgn},@var{comp})
\JP :: 構造体に体する基本演算を登録する. 
\EG :: Registers a set of fundamental operations for a type of structure.
@end table

@table @var
@item return
\JP 1
\EG 1
@item name
\JP 文字列
\EG string
@item add  sub  mul  div  pwr  chsgn  comp
\JP ユーザ定義関数
\EG user defined functions
@end table

@itemize @bullet
@item 
\JP @var{name} なる構造体型に対する基本演算を登録する. 
\BEG
This function registers a set of fundamental operations for a type
of structure whose name is @var{name}.
\E
\BJP
@item
登録したくない基本演算に対しては引数に 0 を与える.
これによって一部の演算のみを利用することができる.
\E
@item
\JP それぞれの関数の仕様は次の通りである. 
\EG The specification of each function is as follows.
@table @code
@item add(A,B)
A+B
@item sub(A,B)
A-B
@item mul(A,B)
A*B
@item div(A,B)
A/B
@item pwr(A,B)
A^B
@item chsgn(A)
-A
@item comp(A,B)
1,0,-1 according to the result of a comparison between A and B.
@end table
@end itemize

@example
% cat test
struct a @{id,body@}$

def add(A,B)
@{
  C = newstruct(a);
  C->id = A->id; C->body = A->body+B->body;
  return C;
@}

def sub(A,B)
@{
  C = newstruct(a);
  C->id = A->id; C->body = A->body-B->body;
  return C;
@}

def mul(A,B)
@{
  C = newstruct(a);
  C->id = A->id; C->body = A->body*B->body;
  return C;
@}

def div(A,B)
@{
  C = newstruct(a);
  C->id = A->id; C->body = A->body/B->body;
  return C;
@}

def pwr(A,B)
@{
  C = newstruct(a);
  C->id = A->id; C->body = A->body^B;
  return C;
@}

def chsgn(A)
@{
  C = newstruct(a);
  C->id = A->id; C->body = -A->body;
  return C;
@}

def comp(A,B)
@{
  if ( A->body > B->body )
    return 1;
  else if ( A->body < B->body )
    return -1;
  else
    return 0;
@}

arfreg("a",add,sub,mul,div,pwr,chsgn,comp)$
end$
% asir
This is Risa/Asir, Version 20000908.
Copyright (C) FUJITSU LABORATORIES LIMITED.
1994-2000. All rights reserved.
[0] load("./test")$
[11] A=newstruct(a);
@{0,0@}
[12] B=newstruct(a);
@{0,0@}
[13] A->body = 3;
3
[14] B->body = 4;
4
[15] A*B;
@{0,12@}
@end example

@table @t
\JP @item 参照
\EG @item References
@fref{newstruct},
\JP @fref{構造体定義}
\EG @fref{structure definition}
@end table