dicthelpers: inline diff and join code mpm suggested this change since it improves performance slightly. Benchmarking hg perfcalculate -r . Before: ! wall 0.141173 comb 0.140000 user 0.140000 sys 0.000000 (best of 66) After: ! wall 0.138619 comb 0.140000 user 0.140000 sys 0.000000 (best of 69)