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22 changes: 13 additions & 9 deletions README.md
Original file line number Diff line number Diff line change
Expand Up @@ -655,18 +655,22 @@ Enumerable#select.first: 89757.4 i/s - 4.84x slower

```
$ ruby -v code/enumerable/select-last-vs-reverse-detect.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]

ruby 3.4.2 (2025-02-15 revision d2930f8e7a) +PRISM [arm64-darwin23]
ruby 3.4.2 (2025-02-15 revision d2930f8e7a) +PRISM [arm64-darwin23]
Warming up --------------------------------------
Enumerable#reverse.detect
8.821k i/100ms
Enumerable#select.last
385.000 i/100ms
Calculating -------------------------------------
Enumerable#reverse.detect 62.636k i/100ms
Enumerable#select.last 11.687k i/100ms
-------------------------------------------------
Enumerable#reverse.detect 1.263M (± 8.2%) i/s - 6.326M
Enumerable#select.last 119.387k (± 5.7%) i/s - 596.037k
Enumerable#reverse.detect
96.317k (± 6.8%) i/s (10.38 μs/i) - 485.155k in 5.060103s
Enumerable#select.last
3.839k (± 1.2%) i/s (260.49 μs/i) - 19.250k in 5.015198s

Comparison:
Enumerable#reverse.detect: 1263100.2 i/s
Enumerable#select.last: 119386.8 i/s - 10.58x slower
Enumerable#reverse.detect: 96316.5 i/s
Enumerable#select.last: 3838.9 i/s - 25.09x slower
```

##### `Enumerable#sort` vs `Enumerable#sort_by` [code](code/enumerable/sort-vs-sort_by.rb)
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6 changes: 3 additions & 3 deletions code/enumerable/select-last-vs-reverse-detect.rb
Original file line number Diff line number Diff line change
@@ -1,13 +1,13 @@
require 'benchmark/ips'

ARRAY = [*1..100]
ARRAY = [*1..7777]

def fast
ARRAY.reverse.detect { |x| (x % 10).zero? }
ARRAY.reverse.detect { |x| (x % 5).zero? }
end

def slow
ARRAY.select { |x| (x % 10).zero? }.last
ARRAY.select { |x| (x % 5).zero? }.last
end

Benchmark.ips do |x|
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