| 270 | values = [m.leftmost() for m in mappings] |
| 271 | |
| 272 | def changes(): |
| 273 | |
| 274 | def start_i_value(i_m): |
| 275 | i, m = i_m |
| 276 | res = ((k.start, i, v) for k, v in m.iteritems(True)) |
| 277 | next(res) |
| 278 | return res |
| 279 | change_points = merge(*map(start_i_value, enumerate(mappings))) |
| 280 | |
| 281 | lastbound = None |
| 282 | for bound, i, v in change_points: |
| 283 | values[i] = v |
| 284 | if bound != lastbound: |
| 285 | yield bound, func(*values) |
| 286 | lastbound = bound |
| 287 | yield bound, func(*values) |
| 288 | |
| 289 | return IntervalMapping.from_changes(func(*values), changes()) |
| 290 | |