Guido van Rossum | 12d12c5 | 1993-10-26 17:58:25 +0000 | [diff] [blame^] | 1 | /*********************************************************** |
| 2 | Copyright 1991, 1992, 1993 by Stichting Mathematisch Centrum, |
| 3 | Amsterdam, The Netherlands. |
| 4 | |
| 5 | All Rights Reserved |
| 6 | |
| 7 | Permission to use, copy, modify, and distribute this software and its |
| 8 | documentation for any purpose and without fee is hereby granted, |
| 9 | provided that the above copyright notice appear in all copies and that |
| 10 | both that copyright notice and this permission notice appear in |
| 11 | supporting documentation, and that the names of Stichting Mathematisch |
| 12 | Centrum or CWI not be used in advertising or publicity pertaining to |
| 13 | distribution of the software without specific, written prior permission. |
| 14 | |
| 15 | STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO |
| 16 | THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND |
| 17 | FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE |
| 18 | FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 19 | WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| 20 | ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT |
| 21 | OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| 22 | |
| 23 | ******************************************************************/ |
| 24 | |
| 25 | /* Range object implementation */ |
| 26 | |
| 27 | #include "allobjects.h" |
| 28 | |
| 29 | typedef struct { |
| 30 | OB_HEAD |
| 31 | long start; |
| 32 | long step; |
| 33 | long len; |
| 34 | int reps; |
| 35 | } rangeobject; |
| 36 | |
| 37 | |
| 38 | object * |
| 39 | newrangeobject(start, len, step, reps) |
| 40 | long start, len, step; |
| 41 | int reps; |
| 42 | { |
| 43 | rangeobject *obj = (rangeobject *) newobject(&Rangetype); |
| 44 | |
| 45 | obj->start = start; |
| 46 | obj->len = len; |
| 47 | obj->step = step; |
| 48 | obj->reps = reps; |
| 49 | |
| 50 | return (object *) obj; |
| 51 | } |
| 52 | |
| 53 | static void |
| 54 | range_dealloc(r) |
| 55 | rangeobject *r; |
| 56 | { |
| 57 | DEL(r); |
| 58 | } |
| 59 | |
| 60 | static object * |
| 61 | range_item(r, i) |
| 62 | rangeobject *r; |
| 63 | int i; |
| 64 | { |
| 65 | if (i < 0 || i >= r->len * r->reps) { |
| 66 | err_setstr(IndexError, "range object index out of range"); |
| 67 | return NULL; |
| 68 | } |
| 69 | |
| 70 | return newintobject(r->start + (i % r->len) * r->step); |
| 71 | } |
| 72 | |
| 73 | static int |
| 74 | range_length(r) |
| 75 | rangeobject *r; |
| 76 | { |
| 77 | return r->len * r->reps; |
| 78 | } |
| 79 | |
| 80 | static object * |
| 81 | range_repr(r) |
| 82 | rangeobject *r; |
| 83 | { |
| 84 | char buf[80]; |
| 85 | if (r->reps != 1) |
| 86 | sprintf(buf, "(xrange(%ld, %ld, %ld) * %d)", |
| 87 | r->start, |
| 88 | r->start + r->len * r->step, |
| 89 | r->step, |
| 90 | r->reps); |
| 91 | else |
| 92 | sprintf(buf, "xrange(%ld, %ld, %ld)", |
| 93 | r->start, |
| 94 | r->start + r->len * r->step, |
| 95 | r->step); |
| 96 | return newstringobject(buf); |
| 97 | } |
| 98 | |
| 99 | object * |
| 100 | range_concat(r, obj) |
| 101 | rangeobject *r; |
| 102 | object *obj; |
| 103 | { |
| 104 | if (is_rangeobject(obj)) { |
| 105 | rangeobject *s = (rangeobject *)obj; |
| 106 | if (r->start == s->start && r->len == s->len && |
| 107 | r->step == s->step) |
| 108 | return newrangeobject(r->start, r->len, r->step, |
| 109 | r->reps + s->reps); |
| 110 | } |
| 111 | err_setstr(TypeError, "cannot concatenate different range objects"); |
| 112 | return NULL; |
| 113 | } |
| 114 | |
| 115 | object * |
| 116 | range_repeat(r, n) |
| 117 | rangeobject *r; |
| 118 | int n; |
| 119 | { |
| 120 | if (n < 0) |
| 121 | return (object *) newrangeobject(0, 0, 1, 1); |
| 122 | |
| 123 | else if (n == 1) { |
| 124 | INCREF(r); |
| 125 | return (object *) r; |
| 126 | } |
| 127 | |
| 128 | else |
| 129 | return (object *) newrangeobject( |
| 130 | r->start, |
| 131 | r->len, |
| 132 | r->step, |
| 133 | r->reps * n); |
| 134 | } |
| 135 | |
| 136 | static int |
| 137 | range_compare(r1, r2) |
| 138 | rangeobject *r1, *r2; |
| 139 | { |
| 140 | if (r1->start != r2->start) |
| 141 | return r1->start - r2->start; |
| 142 | |
| 143 | else if (r1->step != r2->step) |
| 144 | return r1->step - r2->step; |
| 145 | |
| 146 | else if (r1->len != r2->len) |
| 147 | return r1->len - r2->len; |
| 148 | |
| 149 | else |
| 150 | return r1->reps - r2->reps; |
| 151 | } |
| 152 | |
| 153 | static object * |
| 154 | range_slice(r, low, high) |
| 155 | rangeobject *r; |
| 156 | int low, high; |
| 157 | { |
| 158 | if (r->reps != 1) { |
| 159 | err_setstr(TypeError, "cannot slice a replicated range"); |
| 160 | return NULL; |
| 161 | } |
| 162 | if (low < 0) |
| 163 | low = 0; |
| 164 | else if (low > r->len) |
| 165 | low = r->len; |
| 166 | if (high < 0) |
| 167 | high = 0; |
| 168 | if (high < low) |
| 169 | high = low; |
| 170 | else if (high > r->len) |
| 171 | high = r->len; |
| 172 | |
| 173 | return (object *) newrangeobject( |
| 174 | low * r->step + r->start, |
| 175 | high - low, |
| 176 | r->step, |
| 177 | 1); |
| 178 | } |
| 179 | |
| 180 | static sequence_methods range_as_sequence = { |
| 181 | range_length, /*sq_length*/ |
| 182 | range_concat, /*sq_concat*/ |
| 183 | range_repeat, /*sq_repeat*/ |
| 184 | range_item, /*sq_item*/ |
| 185 | range_slice, /*sq_slice*/ |
| 186 | 0, /*sq_ass_item*/ |
| 187 | 0, /*sq_ass_slice*/ |
| 188 | }; |
| 189 | |
| 190 | typeobject Rangetype = { |
| 191 | OB_HEAD_INIT(&Typetype) |
| 192 | 0, /* Number of items for varobject */ |
| 193 | "range", /* Name of this type */ |
| 194 | sizeof(rangeobject), /* Basic object size */ |
| 195 | 0, /* Item size for varobject */ |
| 196 | range_dealloc, /*tp_dealloc*/ |
| 197 | 0, /*tp_print*/ |
| 198 | 0, /*tp_getattr*/ |
| 199 | 0, /*tp_setattr*/ |
| 200 | range_compare, /*tp_compare*/ |
| 201 | range_repr, /*tp_repr*/ |
| 202 | 0, /*tp_as_number*/ |
| 203 | &range_as_sequence, /*tp_as_sequence*/ |
| 204 | 0, /*tp_as_mapping*/ |
| 205 | }; |