diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | array.c | 16 |
2 files changed, 17 insertions, 5 deletions
@@ -1,3 +1,9 @@ +Mon Nov 19 16:04:08 2007 Yukihiro Matsumoto <matz@ruby-lang.org> + + * array.c (rb_ary_permutation): gives all permutations of elements + if no argument given. a patch from Yusuke ENDOH <mame AT tsg.ne.jp>. + [ruby-dev:32309] + Mon Nov 19 02:44:07 2007 Nobuyoshi Nakada <nobu@ruby-lang.org> * compile.c (iseq_compile_each): alias and undef accept dsyms as well @@ -3001,11 +3001,14 @@ permute0(long n, long r, long *p, long index, int *used, VALUE values) /* * call-seq: + * ary.permutation { |p| block } -> array + * ary.permutation -> enumerator * ary.permutation(n) { |p| block } -> array * ary.permutation(n) -> enumerator * * When invoked with a block, yield all permutations of length <i>n</i> * of the elements of <i>ary</i>, then return the array itself. + * If <i>n</i> is not specified, yield all permutations of all elements. * The implementation makes no guarantees about the order in which * the permutations are yielded. * @@ -3013,6 +3016,7 @@ permute0(long n, long r, long *p, long index, int *used, VALUE values) * * Examples: * a = [1, 2, 3] + * a.permutation.to_a #=> [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]] * a.permutation(1).to_a #=> [[1],[2],[3]] * a.permutation(2).to_a #=> [[1,2],[1,3],[2,1],[2,3],[3,1],[3,2]] * a.permutation(3).to_a #=> [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]] @@ -3021,13 +3025,15 @@ permute0(long n, long r, long *p, long index, int *used, VALUE values) */ static VALUE -rb_ary_permutation(VALUE ary, VALUE num) +rb_ary_permutation(int argc, VALUE *argv, VALUE ary) { + VALUE num; long r, n, i; - RETURN_ENUMERATOR(ary, 1, &num); /* Return enumerator if no block */ - r = NUM2LONG(num); /* Permutation size from argument */ - n = RARRAY_LEN(ary); /* Array length */ + RETURN_ENUMERATOR(ary, argc, argv); /* Return enumerator if no block */ + n = RARRAY_LEN(ary); /* Array length */ + rb_scan_args(argc, argv, "01", &num); + r = NIL_P(num) ? n : NUM2LONG(num); /* Permutation size from argument */ if (r < 0 || n < r) { /* no permutations: yield nothing */ @@ -3310,7 +3316,7 @@ Init_Array(void) rb_define_method(rb_cArray, "shuffle", rb_ary_shuffle, 0); rb_define_method(rb_cArray, "choice", rb_ary_choice, 0); rb_define_method(rb_cArray, "cycle", rb_ary_cycle, 0); - rb_define_method(rb_cArray, "permutation", rb_ary_permutation, 1); + rb_define_method(rb_cArray, "permutation", rb_ary_permutation, -1); rb_define_method(rb_cArray, "combination", rb_ary_combination, 1); rb_define_method(rb_cArray, "product", rb_ary_product, -1); |