`car', `cdr', `cons', `append', `reverse', `length'
---------------------------------------------------

car(LIST)
     :: łȂ LIST ̐擪vf.
cdr(LIST)
     :: łȂ LIST 擪vf菜Xg.
cons(OBJ,LIST)
     :: LIST ̐擪 OBJ tXg.
append(LIST1,LIST2)
     :: LIST1  LIST2 ̏ 1 ɂXg.
reverse(LIST)
     :: LIST tɂXg.
length(LIST)
     :: LIST ̒.

RETURN
     `car()' : C, `cdr()', `cons()', `append()', `reverse()' : X
     g, `length()' : R
LIST,LIST1,LIST2
     Xg
OBJ
     C

   * Xg [OBJ1,OBJ2,...] ƕ\. OBJ1 擪vfł.
   * `car()' , łȂ LIST ̐擪vfo͂. 󃊃Xg͂
     ꂽꍇ, 󃊃Xgo͂.
   * `cdr()' , łȂ LIST 擪vf菜Xgo͂
     . 󃊃Xg͂ꂽꍇ, 󃊃Xgo͂.
   * `cons()' , LIST ̐擪 OBJ tXgo͂.
   * `append()' , LIST1 ̗vf LIST2 ׂ̂Ă̗vf
     Xg [LIST1 ̗vf̕,LIST2 ̗vf̕] o͂.
   * `reverse()' , LIST tɂXgo͂.
   * `length()' , LIST ̒o͂. xNgyэs̗vf̌
     , `size()' p.
   * Xg͓ǂݏop, vf̓ւ͂łȂ.
   * Xg N Ԗڂ̗vf̎o, `cdr()'  N Kp 
     `car()' Kp邱Ƃɂ\ł邪, ֖@Ƃ, xNg, 
     sȂǂ̔zƓl, CfbNX `[N]' ɕt邱Ƃɂ
     oƂł. , VXeł, ۂɃ|C^ 
     N 񂽂ǂ̂, ̗vfقǎoɎԂ.
   * `cdr()' ͐VZ𐶐Ȃ, `append()' , ۂɂ͑ 1 
     ̃Xg̒ `cons()' ̌JԂƂȂ邽,  1 
     ̃Xgꍇɂ͑̃邱ƂɂȂ. 
     `reverse()' ɊւĂlł.

     [0] L = [[1,2,3],4,[5,6]];
     [[1,2,3],4,[5,6]]
     [1] car(L);
     [1,2,3]
     [2] cdr(L);
     [4,[5,6]]
     [3] cons(x*y,L);
     [y*x,[1,2,3],4,[5,6]]
     [4] append([a,b,c],[d]);
     [a,b,c,d]
     [5] reverse([a,b,c,d]);
     [d,c,b,a]
     [6] length(L);
     3
     [7] L[2][0];
     5

