These benchmarks are a bit noisy and imperfect. We focus on the big changes.

extend-after-1.log is taking advantage of TrustedLen in Vec::extend.


name                            extend-before-1.log ns/iter  extend-after-1.log ns/iter    diff ns/iter   diff %
bench_chain_all                 17,866                       17,917                                  51    0.29%
bench_chain_chain_collect       62,249                       32,370                             -29,879  -48.00%
bench_chain_collect             26,828                       25,386                              -1,442   -5.37%
bench_chain_extend_ref          18,070                       18,606                                 536    2.97%
bench_chain_extend_value        23,146                       18,101                              -5,045  -21.80%
bench_chain_fold                1,417                        1,384                                  -33   -2.33%
bench_collect                   228,065                      234,066                              6,001    2.63%
bench_extend_from_slice         2,578                        2,639                                   61    2.37%
bench_extend_with_vec_1         17                           18                                       1    5.88%
bench_extend_with_vec_2         5,111                        5,520                                  409    8.00%
bench_map_fast                  6,061                        6,245                                  184    3.04%
bench_map_regular               14,108                       6,429                               -7,679  -54.43%
bench_nest_chain_chain_collect  44,562                       41,087                              -3,475   -7.80%
bench_push_loop                 102,615                      104,471                              1,856    1.81%
bench_range_map_collect         12,794                       1,992                              -10,802  -84.43%
bench_rev_1                     14,143                       2,792                              -11,351  -80.26%
bench_rev_2                     14,089                       2,773                              -11,316  -80.32%
bench_slice_all                 8,893                        8,964                                   71    0.80%
bench_slice_fold                1,383                        1,379                                   -4   -0.29%