% bencher -Ilib -m PERLANCAR/grep_bool 
+------------------------+----------+------------+-------------+------------+---------+---------+
| participant            | dataset  | rate (/s)  |   time (ms) | vs_slowest |  errors | samples |
+------------------------+----------+------------+-------------+------------+---------+---------+
| Array::AllUtils::first | notfound |     556    | 1.8         |    1       | 1.3e-06 |      21 |
| Array::AllUtils::first | last     |     559    | 1.79        |    1.01    | 2.7e-07 |      20 |
| grep+die               | last     |     672    | 1.49        |    1.21    | 4.3e-07 |      20 |
| grep+die               | notfound |     677    | 1.48        |    1.22    | 4.8e-07 |      20 |
| foreach+last+do        | last     |    3124.33 | 0.320068    |    5.62082 |   0     |      21 |
| foreach+last+do        | notfound |    3130    | 0.32        |    5.63    | 5.3e-08 |      20 |
| grep                   | first    |    3330    | 0.301       |    5.98    | 5.3e-08 |      20 |
| grep                   | notfound |    3572.41 | 0.279923    |    6.42693 |   0     |      21 |
| grep                   | last     |    3580    | 0.28        |    6.44    | 5.3e-08 |      20 |
| List::Util::first      | last     |    4237.74 | 0.235975    |    7.62389 |   0     |      20 |
| List::Util::first      | notfound |    4237.74 | 0.235975    |    7.62389 |   0     |      20 |
| List::Util::first      | first    |   51781.5  | 0.0193119   |   93.1573  |   0     |      20 |
| grep+die               | first    |  130000    | 0.0079      |  230       | 1.3e-08 |      20 |
| Array::AllUtils::first | first    | 2170000    | 0.000461    | 3900       |   2e-10 |      21 |
| foreach+last+do        | first    | 5478270    | 0.000182539 | 9855.67    |   0     |      20 |
+------------------------+----------+------------+-------------+------------+---------+---------+

This basically benchmarks over an array containing 10,000 items with three cases: first is when the item to be found is at the first element, last is when the item to be found is at the last element, and notfound is when the item searched does not exist in the array (which should be the same performance-wise as last, but added for testing the result).

You can see that List::Util::first is much slower than Array::AllUtils::first or foreach+last+do or grep+die for the 'first' case.

The benchmark scenario is here.

Thanks, did you also test firstval() from List::MoreUtils ?

Cheers Rolf
_{(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!}

I was not aware of List::MoreUtils::firstval. Okay, added it to the benchmark. It mostly has the same speed as List::Util::first, I wonder what the differences are.

% bencher -Ilib -m PERLANCAR/grep_bool --include-participant-pattern List::
+---------------------------+----------+-----------+-----------+------------+---------+---------+
| participant               | dataset  | rate (/s) | time (μs) | vs_slowest |  errors | samples |
+---------------------------+----------+-----------+-----------+------------+---------+---------+
| List::Util::first         | notfound |      3900 |   250     |      1     | 1.8e-06 |      20 |
| List::MoreUtils::firstval | last     |      3980 |   251     |      1.01  | 5.3e-08 |      20 |
| List::MoreUtils::firstval | notfound |      4000 |   250     |      1     | 1.1e-06 |      20 |
| List::Util::first         | last     |      4100 |   240     |      1     | 4.8e-07 |      20 |
| List::Util::first         | first    |     46400 |    21.6   |     11.8   | 2.1e-08 |      31 |
| List::MoreUtils::firstval | first    |     46406 |    21.549 |     11.788 | 1.5e-10 |      20 |
+---------------------------+----------+-----------+-----------+------------+---------+---------+