Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/fastruby/fast-ruby
:dash: Writing Fast Ruby :heart_eyes: -- Collect Common Ruby idioms.
https://github.com/fastruby/fast-ruby
benchmark-ips hacktoberfest performance-optimization ruby
Last synced: 27 days ago
JSON representation
:dash: Writing Fast Ruby :heart_eyes: -- Collect Common Ruby idioms.
- Host: GitHub
- URL: https://github.com/fastruby/fast-ruby
- Owner: fastruby
- Created: 2014-10-13T11:19:28.000Z (about 10 years ago)
- Default Branch: main
- Last Pushed: 2023-12-11T09:07:31.000Z (11 months ago)
- Last Synced: 2024-05-17T15:24:47.239Z (6 months ago)
- Topics: benchmark-ips, hacktoberfest, performance-optimization, ruby
- Language: Ruby
- Homepage: https://github.com/fastruby/fast-ruby
- Size: 1.35 MB
- Stars: 5,651
- Watchers: 174
- Forks: 375
- Open Issues: 48
-
Metadata Files:
- Readme: README.md
- Contributing: CONTRIBUTING.md
Awesome Lists containing this project
- awesome-ruby - fast-ruby - Writing Fast Ruby. Collect Common Ruby idioms. (Coding Style Guides)
- my-awesome-github-stars - fastruby/fast-ruby - :dash: Writing Fast Ruby :heart_eyes: -- Collect Common Ruby idioms. (Ruby)
README
Fast Ruby [](https://github.com/fastruby/fast-ruby/actions/workflows/benchmarks.yml)
=======================================================================================================================================================================
In [Erik Michaels-Ober](https://github.com/sferik)'s great talk, 'Writing Fast Ruby': [Video @ Baruco 2014](https://www.youtube.com/watch?v=fGFM_UrSp70), [Slide](https://speakerdeck.com/sferik/writing-fast-ruby), he presented us with many idioms that lead to faster running Ruby code. He inspired me to document these to let more people know. I try to link to real commits so people can see that this can really have benefits in the real world. **This does not mean you can always blindly replace one with another. It depends on the context (e.g. `gsub` versus `tr`). Friendly reminder: Use with caution!**
Each idiom has a corresponding code example that resides in [code](code).
All results listed in README.md are running with Ruby 2.2.0p0 on OS X 10.10.1. Machine information: MacBook Pro (Retina, 15-inch, Mid 2014), 2.5 GHz Intel Core i7, 16 GB 1600 MHz DDR3. Your results may vary, but you get the idea. : )
You can checkout [the GitHub Actions build](https://github.com/fastruby/fast-ruby/actions) for these benchmark results ran against different Ruby implementations.
**Let's write faster code, together! <3**
Analyze your code
-----------------
Checkout the [fasterer](https://github.com/DamirSvrtan/fasterer) project - it's a static analysis that checks speed idioms written in this repo.
Measurement Tool
-----------------
Use [benchmark-ips](https://github.com/evanphx/benchmark-ips) (2.0+).
### Template
```ruby
require "benchmark/ips"
def fast
end
def slow
end
Benchmark.ips do |x|
x.report("fast code description") { fast }
x.report("slow code description") { slow }
x.compare!
end
```
Idioms
------
### Index
- [General](#general)
- [Array](#array)
- [Date](#date)
- [Enumerable](#enumerable)
- [Hash](#hash)
- [Proc & Block](#proc--block)
- [String](#string)
- [Time](#time)
- [Range](#range)
### General
##### `attr_accessor` vs `getter and setter` [code](code/general/attr-accessor-vs-getter-and-setter.rb)
> https://www.omniref.com/ruby/2.2.0/files/method.h?#annotation=4081781&line=47
```
$ ruby -v code/general/attr-accessor-vs-getter-and-setter.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
getter_and_setter 61.240k i/100ms
attr_accessor 66.535k i/100ms
-------------------------------------------------
getter_and_setter 1.660M (± 9.7%) i/s - 8.267M
attr_accessor 1.865M (± 9.2%) i/s - 9.248M
Comparison:
attr_accessor: 1865408.4 i/s
getter_and_setter: 1660021.9 i/s - 1.12x slower
```
##### `begin...rescue` vs `respond_to?` for Control Flow [code](code/general/begin-rescue-vs-respond-to.rb)
```
$ ruby -v code/general/begin-rescue-vs-respond-to.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
begin...rescue 29.452k i/100ms
respond_to? 106.528k i/100ms
-------------------------------------------------
begin...rescue 371.591k (± 5.4%) i/s - 1.855M
respond_to? 3.277M (± 7.5%) i/s - 16.299M
Comparison:
respond_to?: 3276972.3 i/s
begin...rescue: 371591.0 i/s - 8.82x slower
```
##### `define_method` vs `module_eval` for Defining Methods [code](code/general/define_method-vs-module-eval.rb)
```
$ ruby -v code/general/define_method-vs-module-eval.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
module_eval with string 125.000 i/100ms
define_method 138.000 i/100ms
-------------------------------------------------
module_eval with string 1.130k (±20.3%) i/s - 5.500k
define_method 1.346k (±25.9%) i/s - 6.348k
Comparison:
define_method: 1345.6 i/s
module_eval with string: 1129.7 i/s - 1.19x slower
```
##### `String#constantize` vs a comparison for inflection [code](code/general/constantize-vs-comparison.rb)
ActiveSupport's [String#constantize](https://guides.rubyonrails.org/active_support_core_extensions.html#constantize) "resolves the constant reference expression in its receiver".
[Read the rationale here](https://github.com/fastruby/fast-ruby/pull/200)
```
ruby 2.7.3p183 (2021-04-05 revision 6847ee089d) [x86_64-darwin20]
Calculating -------------------------------------
using an if statement
8.124M (± 1.8%) i/s - 41.357M in 5.092437s
String#constantize 2.462M (± 2.4%) i/s - 12.315M in 5.004089s
Comparison:
using an if statement: 8123851.3 i/s
String#constantize: 2462371.2 i/s - 3.30x (± 0.00) slower
```
##### `raise` vs `E2MM#Raise` for raising (and defining) exceptions [code](code/general/raise-vs-e2mmap.rb)
Ruby's [Exception2MessageMapper module](http://ruby-doc.org/stdlib-2.2.0/libdoc/e2mmap/rdoc/index.html) allows one to define and raise exceptions with predefined messages.
```
$ ruby -v code/general/raise-vs-e2mmap.rb
ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-darwin14]
Calculating -------------------------------------
Ruby exception: E2MM#Raise
2.865k i/100ms
Ruby exception: Kernel#raise
42.215k i/100ms
-------------------------------------------------
Ruby exception: E2MM#Raise
27.270k (± 8.8%) i/s - 137.520k
Ruby exception: Kernel#raise
617.446k (± 7.9%) i/s - 3.082M
Comparison:
Ruby exception: Kernel#raise: 617446.2 i/s
Ruby exception: E2MM#Raise: 27269.8 i/s - 22.64x slower
Calculating -------------------------------------
Custom exception: E2MM#Raise
2.807k i/100ms
Custom exception: Kernel#raise
45.313k i/100ms
-------------------------------------------------
Custom exception: E2MM#Raise
29.005k (± 7.2%) i/s - 145.964k
Custom exception: Kernel#raise
589.149k (± 7.8%) i/s - 2.945M
Comparison:
Custom exception: Kernel#raise: 589148.7 i/s
Custom exception: E2MM#Raise: 29004.8 i/s - 20.31x slower
```
##### `loop` vs `while true` [code](code/general/loop-vs-while-true.rb)
```
$ ruby -v code/general/loop-vs-while-true.rb
ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-linux]
Calculating -------------------------------------
While Loop 1.000 i/100ms
Kernel loop 1.000 i/100ms
-------------------------------------------------
While Loop 0.536 (± 0.0%) i/s - 3.000 in 5.593042s
Kernel loop 0.223 (± 0.0%) i/s - 2.000 in 8.982355s
Comparison:
While Loop: 0.5 i/s
Kernel loop: 0.2 i/s - 2.41x slower
```
##### `ancestors.include?` vs `<=` [code](code/general/inheritance-check.rb)
```
$ ruby -vW0 code/general/inheritance-check.rb
ruby 2.5.0p0 (2017-12-25 revision 61468) [x86_64-linux]
Warming up --------------------------------------
less than or equal 66.992k i/100ms
ancestors.include? 16.943k i/100ms
Calculating -------------------------------------
less than or equal 1.250M (± 6.4%) i/s - 6.230M in 5.006896s
ancestors.include? 192.603k (± 4.8%) i/s - 965.751k in 5.025917s
Comparison:
less than or equal: 1249606.0 i/s
ancestors.include?: 192602.9 i/s - 6.49x slower
```
### Method Invocation
##### `call` vs `send` vs `method_missing` [code](code/method/call-vs-send-vs-method_missing.rb)
```
$ ruby -v code/method/call-vs-send-vs-method_missing.rb
ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-darwin14]
Calculating -------------------------------------
call 115.094k i/100ms
send 105.258k i/100ms
method_missing 100.762k i/100ms
-------------------------------------------------
call 3.811M (± 5.9%) i/s - 18.991M
send 3.244M (± 7.2%) i/s - 16.210M
method_missing 2.729M (± 9.8%) i/s - 13.401M
Comparison:
call: 3811183.4 i/s
send: 3244239.1 i/s - 1.17x slower
method_missing: 2728893.0 i/s - 1.40x slower
```
##### Normal way to apply method vs `&method(...)` [code](code/general/block-apply-method.rb)
```
$ ruby -v code/general/block-apply-method.rb
ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-darwin14]
Calculating -------------------------------------
normal 85.749k i/100ms
&method 35.529k i/100ms
-------------------------------------------------
normal 1.867M (± 7.6%) i/s - 9.347M
&method 467.095k (± 6.4%) i/s - 2.345M
Comparison:
normal: 1866669.5 i/s
&method: 467095.4 i/s - 4.00x slower
```
##### Function with single Array argument vs splat arguments [code](code/general/array-argument-vs-splat-arguments.rb)
```
$ ruby -v code/general/array-argument-vs-splat-arguments.rb
ruby 2.1.7p400 (2015-08-18 revision 51632) [x86_64-linux-gnu]
Calculating -------------------------------------
Function with single Array argument
157.231k i/100ms
Function with splat arguments
4.983k i/100ms
-------------------------------------------------
Function with single Array argument
5.581M (± 2.0%) i/s - 27.987M
Function with splat arguments
54.428k (± 3.3%) i/s - 274.065k
Comparison:
Function with single Array argument: 5580972.6 i/s
Function with splat arguments: 54427.7 i/s - 102.54x slower
```
##### Hash vs OpenStruct on access assuming you already have a Hash or an OpenStruct [code](code/general/hash-vs-openstruct-on-access.rb)
```
$ ruby -v code/general/hash-vs-openstruct-on-access.rb
ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-darwin14]
Calculating -------------------------------------
Hash 128.344k i/100ms
OpenStruct 110.723k i/100ms
-------------------------------------------------
Hash 5.279M (± 7.0%) i/s - 26.311M
OpenStruct 3.048M (± 7.0%) i/s - 15.169M
Comparison:
Hash: 5278844.0 i/s
OpenStruct: 3048139.8 i/s - 1.73x slower
```
##### Hash vs OpenStruct (creation) [code](code/general/hash-vs-openstruct.rb)
```
$ ruby -v code/general/hash-vs-openstruct.rb
ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-darwin14]
Calculating -------------------------------------
Hash 75.510k i/100ms
OpenStruct 9.126k i/100ms
-------------------------------------------------
Hash 1.604M (±11.0%) i/s - 7.929M
OpenStruct 96.855k (± 9.9%) i/s - 483.678k
Comparison:
Hash: 1604259.1 i/s
OpenStruct: 96855.3 i/s - 16.56x slower
```
##### Kernel#format vs Float#round().to_s [code](code/general/format-vs-round-and-to-s.rb)
```
$ ruby -v code/general/format-vs-round-and-to-s.rb
ruby 2.3.3p222 (2016-11-21 revision 56859) [x86_64-darwin15]
Warming up --------------------------------------
Float#round 106.645k i/100ms
Kernel#format 84.304k i/100ms
String#% 78.635k i/100ms
Calculating -------------------------------------
Float#round 1.570M (± 3.2%) i/s - 7.892M in 5.030672s
Kernel#format 1.144M (± 3.0%) i/s - 5.733M in 5.015621s
String#% 1.047M (± 4.2%) i/s - 5.269M in 5.042970s
Comparison:
Float#round: 1570411.4 i/s
Kernel#format: 1144036.6 i/s - 1.37x slower
String#%: 1046689.1 i/s - 1.50x slower
```
### Array
##### `Array#bsearch` vs `Array#find` [code](code/array/bsearch-vs-find.rb)
**WARNING:** `bsearch` ONLY works on *sorted array*. More details please see [#29](https://github.com/fastruby/fast-ruby/issues/29).
```
$ ruby -v code/array/bsearch-vs-find.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
find 1.000 i/100ms
bsearch 42.216k i/100ms
-------------------------------------------------
find 0.184 (± 0.0%) i/s - 1.000 in 5.434758s
bsearch 577.301k (± 6.6%) i/s - 2.913M
Comparison:
bsearch: 577300.7 i/s
find: 0.2 i/s - 3137489.63x slower
```
##### `Array#length` vs `Array#size` vs `Array#count` [code](code/array/length-vs-size-vs-count.rb)
Use `#length` when you only want to know how many elements in the array, `#count` could also achieve this. However `#count` should be use for counting specific elements in array. [Note `#size` is an alias of `#length`](https://github.com/ruby/ruby/blob/f8fb526ad9e9f31453bffbc908b6a986736e21a7/array.c#L5817-L5818).
```
$ ruby -v code/array/length-vs-size-vs-count.rb
ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-darwin14]
Calculating -------------------------------------
Array#length 172.998k i/100ms
Array#size 168.130k i/100ms
Array#count 164.911k i/100ms
-------------------------------------------------
Array#length 11.394M (± 6.1%) i/s - 56.743M
Array#size 11.303M (± 6.5%) i/s - 56.324M
Array#count 9.195M (± 8.6%) i/s - 45.680M
Comparison:
Array#length: 11394036.7 i/s
Array#size: 11302701.1 i/s - 1.01x slower
Array#count: 9194976.2 i/s - 1.24x slower
```
##### `Array#shuffle.first` vs `Array#sample` [code](code/array/shuffle-first-vs-sample.rb)
> `Array#shuffle` allocates an extra array.
> `Array#sample` indexes into the array without allocating an extra array.
> This is the reason why Array#sample exists.
> —— @sferik [rails/rails#17245](https://github.com/rails/rails/pull/17245)
```
$ ruby -v code/array/shuffle-first-vs-sample.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Array#shuffle.first 25.406k i/100ms
Array#sample 125.101k i/100ms
-------------------------------------------------
Array#shuffle.first 304.341k (± 4.3%) i/s - 1.524M
Array#sample 5.727M (± 8.6%) i/s - 28.523M
Comparison:
Array#sample: 5727032.0 i/s
Array#shuffle.first: 304341.1 i/s - 18.82x slower
```
##### `Array#[](0)` vs `Array#first` [code](code/array/array-first-vs-index.rb)
```
$ ruby -v code/array/array-first-vs-index.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Array#[0] 152.751k i/100ms
Array#first 148.088k i/100ms
-------------------------------------------------
Array#[0] 8.614M (± 7.0%) i/s - 42.923M
Array#first 7.465M (±10.7%) i/s - 36.874M
Comparison:
Array#[0]: 8613583.7 i/s
Array#first: 7464526.6 i/s - 1.15x slower
```
##### `Array#[](-1)` vs `Array#last` [code](code/array/array-last-vs-index.rb)
```
$ ruby -v code/array/array-last-vs-index.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Array#[-1] 151.940k i/100ms
Array#last 153.371k i/100ms
-------------------------------------------------
Array#[-1] 8.582M (± 4.6%) i/s - 42.847M
Array#last 7.639M (± 5.7%) i/s - 38.189M
Comparison:
Array#[-1]: 8582074.3 i/s
Array#last: 7639254.5 i/s - 1.12x slower
```
##### `Array#insert` vs `Array#unshift` [code](code/array/insert-vs-unshift.rb)
```
$ ruby -v code/array/insert-vs-unshift.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin10.0]
Calculating -------------------------------------
Array#unshift 4.000 i/100ms
Array#insert 1.000 i/100ms
-------------------------------------------------
Array#unshift 44.947 (± 6.7%) i/s - 224.000
Array#insert 0.171 (± 0.0%) i/s - 1.000 in 5.841595s
Comparison:
Array#unshift: 44.9 i/s
Array#insert: 0.2 i/s - 262.56x slower
```
##### `Array#concat` vs `Array#+` [code](code/array/array-concat-vs-+.rb)
`Array#+` returns a new array built by concatenating the two arrays together to
produce a third array. `Array#concat` appends the elements of the other array to self.
This means that the + operator will create a new array each time it is called
(which is expensive), while concat only appends the new element.
```
$ ruby -v code/array/array-concat-vs-+.rb
ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-darwin18]
Warming up --------------------------------------
Array#concat 23.000 i/100ms
Array#+ 1.000 i/100ms
Calculating -------------------------------------
Array#concat 217.669 (±15.2%) i/s - 1.058k in 5.016952s
Array#+ 1.475 (± 0.0%) i/s - 8.000 in 5.467642s
Comparison:
Array#concat: 217.7 i/s
Array#+: 1.5 i/s - 147.54x slower
```
##### `Array#new` vs `Fixnum#times + map` [code](code/array/array-new-vs-fixnum-times-map.rb)
Typical slowdown is 40-60% depending on the size of the array. See the corresponding
[pull request](https://github.com/fastruby/fast-ruby/pull/91/) for performance characteristics.
```
ruby 2.3.0p0 (2015-12-25 revision 53290) [x86_64-darwin15]
Calculating -------------------------------------
Array#new 63.875k i/100ms
Fixnum#times + map 48.010k i/100ms
-------------------------------------------------
Array#new 1.070M (± 2.2%) i/s - 5.365M
Fixnum#times + map 678.097k (± 2.7%) i/s - 3.409M
Comparison:
Array#new: 1069837.0 i/s
Fixnum#times + map: 678097.4 i/s - 1.58x slower
```
##### `Array#sort.reverse` vs `Array#sort_by` + block [code](code/array/sort-reverse-vs-sort_by-with-block.rb)
```
$ ruby -v code/array/sort-reverse-vs-sort_by.rb
ruby 2.5.2p104 (2018-10-18 revision 65133) [x86_64-darwin13]
Warming up --------------------------------------
Array#sort.reverse
16.231k i/100ms
Array#sort_by &:-@
5.406k i/100ms
Calculating -------------------------------------
Array#sort.reverse
149.492k (±11.0%) i/s - 746.626k in 5.070375s
Array#sort_by &:-@
51.981k (± 8.8%) i/s - 259.488k in 5.041625s
Comparison:
Array#sort.reverse: 149492.2 i/s
Array#sort_by &:-@: 51980.6 i/s - 2.88x (± 0.00) slower
```
### Enumerable
##### `Enumerable#each + push` vs `Enumerable#map` [code](code/enumerable/each-push-vs-map.rb)
```
$ ruby -v code/enumerable/each-push-vs-map.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Array#each + push 9.025k i/100ms
Array#map 13.947k i/100ms
-------------------------------------------------
Array#each + push 99.634k (± 3.2%) i/s - 505.400k
Array#map 158.091k (± 4.2%) i/s - 794.979k
Comparison:
Array#map: 158090.9 i/s
Array#each + push: 99634.2 i/s - 1.59x slower
```
##### `Enumerable#each` vs `for` loop [code](code/enumerable/each-vs-for-loop.rb)
```
$ ruby -v code/enumerable/each-vs-for-loop.rb
ruby 2.2.0preview1 (2014-09-17 trunk 47616) [x86_64-darwin14]
Calculating -------------------------------------
For loop 17.111k i/100ms
#each 18.464k i/100ms
-------------------------------------------------
For loop 198.517k (± 5.3%) i/s - 992.438k
#each 208.157k (± 5.0%) i/s - 1.052M
Comparison:
#each: 208157.4 i/s
For loop: 198517.3 i/s - 1.05x slower
```
##### `Enumerable#each_with_index` vs `while` loop [code](code/enumerable/each_with_index-vs-while-loop.rb)
> [rails/rails#12065](https://github.com/rails/rails/pull/12065)
```
$ ruby -v code/enumerable/each_with_index-vs-while-loop.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
While Loop 22.553k i/100ms
each_with_index 11.963k i/100ms
-------------------------------------------------
While Loop 240.752k (± 7.1%) i/s - 1.218M
each_with_index 126.753k (± 5.9%) i/s - 634.039k
Comparison:
While Loop: 240752.1 i/s
each_with_index: 126753.4 i/s - 1.90x slower
```
##### `Enumerable#map`...`Array#flatten` vs `Enumerable#flat_map` [code](code/enumerable/map-flatten-vs-flat_map.rb)
> -- @sferik [rails/rails@3413b88](https://github.com/rails/rails/commit/3413b88), [Replace map.flatten with flat_map](https://github.com/rails/rails/commit/817fe31196dd59ee31f71ef1740122b6759cf16d), [Replace map.flatten(1) with flat_map](https://github.com/rails/rails/commit/b11ebf1d80e4fb124f0ce0448cea30988256da59)
```
$ ruby -v code/enumerable/map-flatten-vs-flat_map.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Array#map.flatten(1) 3.315k i/100ms
Array#map.flatten 3.283k i/100ms
Array#flat_map 5.350k i/100ms
-------------------------------------------------
Array#map.flatten(1) 33.801k (± 4.3%) i/s - 169.065k
Array#map.flatten 34.530k (± 6.0%) i/s - 173.999k
Array#flat_map 55.980k (± 5.0%) i/s - 283.550k
Comparison:
Array#flat_map: 55979.6 i/s
Array#map.flatten: 34529.6 i/s - 1.62x slower
Array#map.flatten(1): 33800.6 i/s - 1.66x slower
```
##### `Enumerable#reverse.each` vs `Enumerable#reverse_each` [code](code/enumerable/reverse-each-vs-reverse_each.rb)
> `Enumerable#reverse` allocates an extra array.
> `Enumerable#reverse_each` yields each value without allocating an extra array.
> This is the reason why `Enumerable#reverse_each` exists.
> -- @sferik [rails/rails#17244](https://github.com/rails/rails/pull/17244)
```
$ ruby -v code/enumerable/reverse-each-vs-reverse_each.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Array#reverse.each 16.746k i/100ms
Array#reverse_each 18.590k i/100ms
-------------------------------------------------
Array#reverse.each 190.729k (± 4.8%) i/s - 954.522k
Array#reverse_each 216.060k (± 4.3%) i/s - 1.078M
Comparison:
Array#reverse_each: 216060.5 i/s
Array#reverse.each: 190729.1 i/s - 1.13x slower
```
##### `Enumerable#sort_by.first` vs `Enumerable#min_by` [code](code/enumerable/sort_by-first-vs-min_by.rb)
`Enumerable#sort_by` performs a sort of the enumerable and allocates a
new array the size of the enumerable. `Enumerable#min_by` doesn't
perform a sort or allocate an array the size of the enumerable.
Similar comparisons hold for `Enumerable#sort_by.last` vs
`Enumerable#max_by`, `Enumerable#sort.first` vs `Enumerable#min`, and
`Enumerable#sort.last` vs `Enumerable#max`.
```
$ ruby -v code/enumerable/sort_by-first-vs-min_by.rb
ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-darwin17]
Warming up --------------------------------------
Enumerable#min_by 15.170k i/100ms
Enumerable#sort_by...first
10.413k i/100ms
Calculating -------------------------------------
Enumerable#min_by 157.877k (± 0.9%) i/s - 804.010k in 5.093048s
Enumerable#sort_by...first
106.831k (± 1.3%) i/s - 541.476k in 5.069403s
Comparison:
Enumerable#min_by: 157877.0 i/s
Enumerable#sort_by...first: 106831.1 i/s - 1.48x slower
```
##### `Enumerable#detect` vs `Enumerable#select.first` [code](code/enumerable/select-first-vs-detect.rb)
```
$ ruby -v code/enumerable/select-first-vs-detect.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Enumerable#select.first 8.515k i/100ms
Enumerable#detect 33.885k i/100ms
-------------------------------------------------
Enumerable#select.first 89.757k (± 5.0%) i/s - 1.797M
Enumerable#detect 434.304k (± 5.2%) i/s - 8.675M
Comparison:
Enumerable#detect: 434304.2 i/s
Enumerable#select.first: 89757.4 i/s - 4.84x slower
```
##### `Enumerable#select.last` vs `Enumerable#reverse.detect` [code](code/enumerable/select-last-vs-reverse-detect.rb)
```
$ ruby -v code/enumerable/select-last-vs-reverse-detect.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
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
Comparison:
Enumerable#reverse.detect: 1263100.2 i/s
Enumerable#select.last: 119386.8 i/s - 10.58x slower
```
##### `Enumerable#sort` vs `Enumerable#sort_by` [code](code/enumerable/sort-vs-sort_by.rb)
```
$ ruby -v code/enumerable/sort-vs-sort_by.rb
ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-darwin14]
Calculating -------------------------------------
Enumerable#sort_by (Symbol#to_proc) 2.680k i/100ms
Enumerable#sort_by 2.462k i/100ms
Enumerable#sort 1.320k i/100ms
-------------------------------------------------
Enumerable#sort_by (Symbol#to_proc) 25.916k (± 4.4%) i/s - 131.320k
Enumerable#sort_by 24.650k (± 5.1%) i/s - 125.562k
Enumerable#sort 14.018k (± 5.6%) i/s - 69.960k
Comparison:
Enumerable#sort_by (Symbol#to_proc): 25916.1 i/s
Enumerable#sort_by: 24650.2 i/s - 1.05x slower
Enumerable#sort: 14018.3 i/s - 1.85x slower
```
##### `Enumerable#inject Symbol` vs `Enumerable#inject Proc` [code](code/enumerable/inject-symbol-vs-block.rb)
Of note, `to_proc` for 1.8.7 is considerable slower than the block format
```
$ ruby -v code/enumerable/inject-symbol-vs-block.rb
ruby 2.2.4p230 (2015-12-16 revision 53155) [x86_64-darwin14]
Warming up --------------------------------------
inject symbol 1.893k i/100ms
inject to_proc 1.583k i/100ms
inject block 1.390k i/100ms
Calculating -------------------------------------
inject symbol 19.001k (± 3.8%) i/s - 96.543k
inject to_proc 15.958k (± 3.5%) i/s - 80.733k
inject block 14.063k (± 3.9%) i/s - 70.890k
Comparison:
inject symbol: 19001.5 i/s
inject to_proc: 15958.3 i/s - 1.19x slower
inject block: 14063.1 i/s - 1.35x slower
```
### Date
##### `Date.iso8601` vs `Date.parse` [code](code/date/iso8601-vs-parse.rb)
When expecting well-formatted data from e.g. an API, `iso8601` is faster and will raise an `ArgumentError` on malformed input.
```
$ ruby -v code/date/iso8601-vs-parse.rb
ruby 2.4.3p205 (2017-12-14 revision 61247) [x86_64-darwin17]
Warming up --------------------------------------
Date.iso8601 28.880k i/100ms
Date.parse 15.805k i/100ms
Calculating -------------------------------------
Date.iso8601 328.035k (± 4.7%) i/s - 1.646M in 5.029287s
Date.parse 175.546k (± 3.8%) i/s - 885.080k in 5.049444s
Comparison:
Date.iso8601: 328035.3 i/s
Date.parse: 175545.9 i/s - 1.87x slower
```
### Hash
##### `Hash#[]` vs `Hash#fetch` [code](code/hash/bracket-vs-fetch.rb)
If you use Ruby 2.2, `Symbol` could be more performant than `String` as `Hash` keys.
Read more regarding this: [Symbol GC in Ruby 2.2](http://www.sitepoint.com/symbol-gc-ruby-2-2/) and [Unraveling String Key Performance in Ruby 2.2](http://www.sitepoint.com/unraveling-string-key-performance-ruby-2-2/).
```
$ ruby -v code/hash/bracket-vs-fetch.rb
ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-darwin14]
Calculating -------------------------------------
Hash#[], symbol 143.850k i/100ms
Hash#fetch, symbol 137.425k i/100ms
Hash#[], string 143.083k i/100ms
Hash#fetch, string 120.417k i/100ms
-------------------------------------------------
Hash#[], symbol 7.531M (± 6.6%) i/s - 37.545M
Hash#fetch, symbol 6.644M (± 8.2%) i/s - 32.982M
Hash#[], string 6.657M (± 7.7%) i/s - 33.195M
Hash#fetch, string 3.981M (± 8.7%) i/s - 19.748M
Comparison:
Hash#[], symbol: 7531355.8 i/s
Hash#[], string: 6656818.8 i/s - 1.13x slower
Hash#fetch, symbol: 6643665.5 i/s - 1.13x slower
Hash#fetch, string: 3981166.5 i/s - 1.89x slower
```
##### `Hash#dig` vs `Hash#[]` vs `Hash#fetch` [code](code/hash/dig-vs-[]-vs-fetch.rb)
[Ruby 2.3 introduced `Hash#dig`](http://ruby-doc.org/core-2.3.0/Hash.html#method-i-dig) which is a readable
and performant option for retrieval from a nested hash, returning `nil` if an extraction step fails.
See [#102 (comment)](https://github.com/fastruby/fast-ruby/pull/102#issuecomment-198827506) for more info.
```
$ ruby -v code/hash/dig-vs-\[\]-vs-fetch.rb
ruby 2.3.0p0 (2015-12-25 revision 53290) [x86_64-darwin15]
Calculating -------------------------------------
Hash#dig 5.719M (± 6.1%) i/s - 28.573M in 5.013997s
Hash#[] 6.066M (± 6.9%) i/s - 30.324M in 5.025614s
Hash#[] || 5.366M (± 6.5%) i/s - 26.933M in 5.041403s
Hash#[] && 2.782M (± 4.8%) i/s - 13.905M in 5.010328s
Hash#fetch 4.101M (± 6.1%) i/s - 20.531M in 5.024945s
Hash#fetch fallback 2.975M (± 5.5%) i/s - 14.972M in 5.048880s
Comparison:
Hash#[]: 6065791.0 i/s
Hash#dig: 5719290.9 i/s - same-ish: difference falls within error
Hash#[] ||: 5366226.5 i/s - same-ish: difference falls within error
Hash#fetch: 4101102.1 i/s - 1.48x slower
Hash#fetch fallback: 2974906.9 i/s - 2.04x slower
Hash#[] &&: 2781646.6 i/s - 2.18x slower
```
##### `Hash[]` vs `Hash#dup` [code](code/hash/bracket-vs-dup.rb)
Source: http://tenderlovemaking.com/2015/02/11/weird-stuff-with-hashes.html
> Does this mean that you should switch to Hash[]?
> Only if your benchmarks can prove that it’s a bottleneck.
> Please please please don’t change all of your code because
> this shows it’s faster. Make sure to measure your app performance first.
```
$ ruby -v code/hash/bracket-vs-dup.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Hash[] 29.403k i/100ms
Hash#dup 16.195k i/100ms
-------------------------------------------------
Hash[] 343.987k (± 8.7%) i/s - 1.735M
Hash#dup 163.516k (±10.2%) i/s - 825.945k
Comparison:
Hash[]: 343986.5 i/s
Hash#dup: 163516.3 i/s - 2.10x slower
```
##### `Hash#fetch` with argument vs `Hash#fetch` + block [code](code/hash/fetch-vs-fetch-with-block.rb)
> Note that the speedup in the block version comes from avoiding repeated
> construction of the argument. If the argument is a constant, number symbol or
> something of that sort the argument version is actually slightly faster
> See also [#39 (comment)](https://github.com/fastruby/fast-ruby/issues/39#issuecomment-103989335)
```
$ ruby -v code/hash/fetch-vs-fetch-with-block.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin13]
Calculating -------------------------------------
Hash#fetch + const 129.868k i/100ms
Hash#fetch + block 125.254k i/100ms
Hash#fetch + arg 121.155k i/100ms
-------------------------------------------------
Hash#fetch + const 7.031M (± 7.0%) i/s - 34.934M
Hash#fetch + block 6.815M (± 4.2%) i/s - 34.069M
Hash#fetch + arg 4.753M (± 5.6%) i/s - 23.746M
Comparison:
Hash#fetch + const: 7030600.4 i/s
Hash#fetch + block: 6814826.7 i/s - 1.03x slower
Hash#fetch + arg: 4752567.2 i/s - 1.48x slower
```
##### `Hash#each_key` instead of `Hash#keys.each` [code](code/hash/keys-each-vs-each_key.rb)
> `Hash#keys.each` allocates an array of keys;
> `Hash#each_key` iterates through the keys without allocating a new array.
> This is the reason why `Hash#each_key` exists.
> —— @sferik [rails/rails#17099](https://github.com/rails/rails/pull/17099)
```
$ ruby -v code/hash/keys-each-vs-each_key.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Hash#keys.each 56.690k i/100ms
Hash#each_key 59.658k i/100ms
-------------------------------------------------
Hash#keys.each 869.262k (± 5.0%) i/s - 4.365M
Hash#each_key 1.049M (± 6.0%) i/s - 5.250M
Comparison:
Hash#each_key: 1049161.6 i/s
Hash#keys.each: 869262.3 i/s - 1.21x slower
```
#### `Hash#key?` instead of `Hash#keys.include?` [code](code/hash/keys-include-vs-key.rb)
> `Hash#keys.include?` allocates an array of keys and performs an O(n) search;
> `Hash#key?` performs an O(1) hash lookup without allocating a new array.
```
$ ruby -v code/hash/keys-include-vs-key.rb
ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-darwin17]
Calculating -------------------------------------
Hash#keys.include? 8.612k (± 2.5%) i/s - 43.248k in 5.024749s
Hash#key? 6.366M (± 5.5%) i/s - 31.715M in 5.002276s
Comparison:
Hash#key?: 6365855.5 i/s
Hash#keys.include?: 8612.4 i/s - 739.15x slower
```
##### `Hash#value?` instead of `Hash#values.include?` [code](code/hash/values-include-vs-value.rb)
> `Hash#values.include?` allocates an array of values and performs an O(n) search;
> `Hash#value?` performs an O(n) search without allocating a new array.
```
$ ruby -v code/hash/values-include-vs-value.rb
ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-darwin17]
Calculating -------------------------------------
Hash#values.include? 23.187k (± 4.3%) i/s - 117.720k in 5.086976s
Hash#value? 38.395k (± 1.0%) i/s - 194.361k in 5.062696s
Comparison:
Hash#value?: 38395.0 i/s
Hash#values.include?: 23186.8 i/s - 1.66x slower
```
##### `Hash#merge!` vs `Hash#[]=` [code](code/hash/merge-bang-vs-\[\]=.rb)
```
$ ruby -v code/hash/merge-bang-vs-\[\]=.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Hash#merge! 1.023k i/100ms
Hash#[]= 2.844k i/100ms
-------------------------------------------------
Hash#merge! 10.653k (± 4.9%) i/s - 53.196k
Hash#[]= 28.287k (±12.4%) i/s - 142.200k
Comparison:
Hash#[]=: 28287.1 i/s
Hash#merge!: 10653.3 i/s - 2.66x slower
```
##### `Hash#update` vs `Hash#[]=` [code](code/hash/update-vs-\[\]=.rb)
```
$ ruby -v code/hash/update-vs-\[\]=.rb
ruby 2.6.6p146 (2020-03-31 revision 67876) [x86_64-darwin18]
Warming up --------------------------------------
Hash#[]= 7.453k i/100ms
Hash#update 4.311k i/100ms
Calculating -------------------------------------
Hash#[]= 74.764k (± 1.9%) i/s - 380.103k in 5.085962s
Hash#update 43.220k (± 0.8%) i/s - 219.861k in 5.087364s
Comparison:
Hash#[]=: 74764.0 i/s
Hash#update: 43220.1 i/s - 1.73x (± 0.00) slower
```
##### `Hash#merge` vs `Hash#**other` [code](code/hash/merge-vs-double-splat-operator.rb)
```
$ ruby -v code/hash/merge-vs-double-splat-operator.rb
ruby 2.3.3p222 (2016-11-21 revision 56859) [x86_64-darwin15]
Warming up --------------------------------------
Hash#**other 64.624k i/100ms
Hash#merge 38.827k i/100ms
Calculating -------------------------------------
Hash#**other 798.397k (± 6.9%) i/s - 4.007M in 5.053516s
Hash#merge 434.171k (± 4.5%) i/s - 2.174M in 5.018927s
Comparison:
Hash#**other: 798396.6 i/s
Hash#merge: 434170.8 i/s - 1.84x slower
```
##### `Hash#merge` vs `Hash#merge!` [code](code/hash/merge-vs-merge-bang.rb)
```
$ ruby -v code/hash/merge-vs-merge-bang.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Hash#merge 39.000 i/100ms
Hash#merge! 1.008k i/100ms
-------------------------------------------------
Hash#merge 409.610 (± 7.6%) i/s - 2.067k
Hash#merge! 9.830k (± 5.8%) i/s - 49.392k
Comparison:
Hash#merge!: 9830.3 i/s
Hash#merge: 409.6 i/s - 24.00x slower
```
##### `{}#merge!(Hash)` vs `Hash#merge({})` vs `Hash#dup#merge!({})` [code](code/hash/merge-bang-vs-merge-vs-dup-merge-bang.rb)
> When we don't want to modify the original hash, and we want duplicates to be created
> See [#42](https://github.com/fastruby/fast-ruby/pull/42#issue-93502261) for more details.
```
$ ruby -v code/hash/merge-bang-vs-merge-vs-dup-merge-bang.rb
ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-linux]
Calculating -------------------------------------
{}#merge!(Hash) do end 2.006k i/100ms
Hash#merge({}) 762.000 i/100ms
Hash#dup#merge!({}) 736.000 i/100ms
-------------------------------------------------
{}#merge!(Hash) do end 20.055k (± 2.0%) i/s - 100.300k in 5.003322s
Hash#merge({}) 7.676k (± 1.2%) i/s - 38.862k in 5.063382s
Hash#dup#merge!({}) 7.440k (± 1.1%) i/s - 37.536k in 5.045851s
Comparison:
{}#merge!(Hash) do end: 20054.8 i/s
Hash#merge({}): 7676.3 i/s - 2.61x slower
Hash#dup#merge!({}): 7439.9 i/s - 2.70x slower
```
##### `Hash#sort_by` vs `Hash#sort` [code](code/hash/hash-key-sort_by-vs-sort.rb)
To sort hash by key.
```
$ ruby -v code/hash/hash-key-sort_by-vs-sort.rb
ruby 2.2.1p85 (2015-02-26 revision 49769) [x86_64-darwin14]
Calculating -------------------------------------
sort_by + to_h 11.468k i/100ms
sort + to_h 8.107k i/100ms
-------------------------------------------------
sort_by + to_h 122.176k (± 6.0%) i/s - 619.272k
sort + to_h 81.973k (± 4.7%) i/s - 413.457k
Comparison:
sort_by + to_h: 122176.2 i/s
sort + to_h: 81972.8 i/s - 1.49x slower
```
##### Native `Hash#slice` vs other slice implementations before native [code](code/hash/slice-native-vs-before-native.rb)
Since ruby 2.5, Hash comes with a `slice` method to select hash members by keys.
```
$ ruby -v code/hash/slice-native-vs-before-native.rb
ruby 2.5.3p105 (2018-10-18 revision 65156) [x86_64-linux]
Warming up --------------------------------------
Hash#native-slice 178.077k i/100ms
Array#each 124.311k i/100ms
Array#each_w/_object 110.818k i/100ms
Hash#select-include 66.972k i/100ms
Calculating -------------------------------------
Hash#native-slice 2.540M (± 1.5%) i/s - 12.822M in 5.049955s
Array#each 1.614M (± 1.0%) i/s - 8.080M in 5.007925s
Array#each_w/_object 1.353M (± 2.6%) i/s - 6.760M in 5.000441s
Hash#select-include 760.944k (± 0.9%) i/s - 3.817M in 5.017123s
Comparison:
Hash#native-slice : 2539515.5 i/s
Array#each : 1613665.5 i/s - 1.57x slower
Array#each_w/_object: 1352851.8 i/s - 1.88x slower
Hash#select-include : 760944.2 i/s - 3.34x slower
```
### Proc & Block
##### Block vs `Symbol#to_proc` [code](code/proc-and-block/block-vs-to_proc.rb)
> `Symbol#to_proc` is considerably more concise than using block syntax.
> ...In some cases, it reduces the number of lines of code.
> —— @sferik [rails/rails#16833](https://github.com/rails/rails/pull/16833)
```
$ ruby -v code/proc-and-block/block-vs-to_proc.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
Block 4.632k i/100ms
Symbol#to_proc 5.225k i/100ms
-------------------------------------------------
Block 47.914k (± 6.3%) i/s - 240.864k
Symbol#to_proc 54.791k (± 4.1%) i/s - 276.925k
Comparison:
Symbol#to_proc: 54791.1 i/s
Block: 47914.3 i/s - 1.14x slower
```
##### `Proc#call` and block arguments vs `yield` [code](code/proc-and-block/proc-call-vs-yield.rb)
In MRI Ruby before 2.5, block arguments [are converted to Procs](https://www.omniref.com/ruby/2.2.0/symbols/Proc/yield?#annotation=4087638&line=711), which incurs a heap allocation.
```
$ ruby -v code/proc-and-block/proc-call-vs-yield.rb
ruby 2.4.4p296 (2018-03-28 revision 63013) [x86_64-darwin18]
Calculating -------------------------------------
block.call 1.967M (± 2.0%) i/s - 9.871M in 5.019328s
block + yield 2.147M (± 3.3%) i/s - 10.814M in 5.044319s
unused block 2.265M (± 1.9%) i/s - 11.333M in 5.004522s
yield 10.436M (± 1.6%) i/s - 52.260M in 5.008851s
Comparison:
yield: 10436414.0 i/s
unused block: 2265399.0 i/s - 4.61x slower
block + yield: 2146619.0 i/s - 4.86x slower
block.call: 1967300.9 i/s - 5.30x slower
```
MRI Ruby 2.5 implements [Lazy Proc allocation for block parameters](https://bugs.ruby-lang.org/issues/14045), which speeds things up by about 3x.:
```
$ ruby -v code/proc-and-block/proc-call-vs-yield.rb
ruby 2.5.3p105 (2018-10-18 revision 65156) [x86_64-darwin18]
Calculating -------------------------------------
block.call 1.970M (± 2.3%) i/s - 9.863M in 5.009599s
block + yield 9.075M (± 2.6%) i/s - 45.510M in 5.018369s
unused block 11.176M (± 2.7%) i/s - 55.977M in 5.012741s
yield 10.588M (± 1.9%) i/s - 53.108M in 5.017755s
Comparison:
unused block: 11176355.0 i/s
yield: 10588342.3 i/s - 1.06x slower
block + yield: 9075355.5 i/s - 1.23x slower
block.call: 1969834.0 i/s - 5.67x slower
```
MRI Ruby 2.6 implements [an optimization for block.call where a block parameter is passed](https://bugs.ruby-lang.org/issues/14330):
```
$ ruby -v code/proc-and-block/proc-call-vs-yield.rb
ruby 2.6.1p33 (2019-01-30 revision 66950) [x86_64-darwin18]
Calculating -------------------------------------
block.call 10.587M (± 1.2%) i/s - 52.969M in 5.003808s
block + yield 12.630M (± 0.3%) i/s - 63.415M in 5.020910s
unused block 15.981M (± 0.8%) i/s - 80.255M in 5.022305s
yield 15.352M (± 3.1%) i/s - 76.816M in 5.009404s
Comparison:
unused block: 15980789.4 i/s
yield: 15351931.0 i/s - 1.04x slower
block + yield: 12630378.1 i/s - 1.27x slower
block.call: 10587315.1 i/s - 1.51x slower
```
### String
##### `String#dup` vs `String#+` [code](code/string/dup-vs-unary-plus.rb)
Note that `String.new` is not the same as the options compared, since it is
always `ASCII-8BIT` encoded instead of the script encoding (usually `UTF-8`).
```
$ ruby -v code/string/dup-vs-unary-plus.rb
ruby 2.4.3p205 (2017-12-14 revision 61247) [x86_64-darwin17]
Calculating -------------------------------------
String#+@ 7.697M (± 1.4%) i/s - 38.634M in 5.020313s
String#dup 3.566M (± 1.0%) i/s - 17.860M in 5.008377s
Comparison:
String#+@: 7697108.3 i/s
String#dup: 3566485.7 i/s - 2.16x slower
```
##### `String#casecmp` vs `String#casecmp?` vs `String#downcase + ==` [code](code/string/casecmp-vs-downcase-==.rb)
`String#casecmp?` is available on Ruby 2.4 or later.
Note that `String#casecmp` only works on characters A-Z/a-z, not all of Unicode.
```
$ ruby -v code/string/casecmp-vs-downcase-\=\=.rb
ruby 2.7.1p83 (2020-03-31 revision a0c7c23c9c) [x86_64-darwin19]
Warming up --------------------------------------
String#casecmp? 395.796k i/100ms
String#downcase + == 543.958k i/100ms
String#casecmp 730.028k i/100ms
Calculating -------------------------------------
String#casecmp? 3.687M (±10.9%) i/s - 18.602M in 5.158065s
String#downcase + == 5.017M (±11.3%) i/s - 25.022M in 5.089175s
String#casecmp 6.948M (± 6.0%) i/s - 35.041M in 5.062714s
Comparison:
String#casecmp: 6948231.0 i/s
String#downcase + ==: 5017089.5 i/s - 1.38x (± 0.00) slower
String#casecmp?: 3686650.7 i/s - 1.88x (± 0.00) slower
```
##### String Concatenation [code](code/string/concatenation.rb)
```
$ ruby -v code/string/concatenation.rb
ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-linux]
Warming up --------------------------------------
String#+ 149.298k i/100ms
String#concat 151.505k i/100ms
String#append 153.389k i/100ms
"foo" "bar" 195.552k i/100ms
"#{'foo'}#{'bar'}" 193.784k i/100ms
Calculating -------------------------------------
String#+ 2.977M (± 1.1%) i/s - 14.930M in 5.015179s
String#concat 3.017M (± 1.3%) i/s - 15.150M in 5.023063s
String#append 3.076M (± 1.2%) i/s - 15.492M in 5.037683s
"foo" "bar" 5.370M (± 1.0%) i/s - 26.986M in 5.026271s
"#{'foo'}#{'bar'}" 5.182M (± 4.6%) i/s - 25.967M in 5.022093s
Comparison:
"foo" "bar": 5369594.5 i/s
"#{'foo'}#{'bar'}": 5181745.7 i/s - same-ish: difference falls within error
String#append: 3075719.2 i/s - 1.75x slower
String#concat: 3016703.5 i/s - 1.78x slower
String#+: 2977282.7 i/s - 1.80x slower
```
##### `String#match` vs `String.match?` vs `String#start_with?`/`String#end_with?` [code (start)](code/string/start-string-checking-match-vs-start_with.rb) [code (end)](code/string/end-string-checking-match-vs-end_with.rb)
The regular expression approaches become slower as the tested string becomes
longer. For short strings, `String#match?` performs similarly to
`String#start_with?`/`String#end_with?`.
> :warning:
> Sometimes you cant replace regexp with `start_with?`,
> for example: `"a\nb" =~ /^b/ #=> 2` but `"a\nb" =~ /\Ab/ #=> nil`.
> :warning:
```
$ ruby -v code/string/start-string-checking-match-vs-start_with.rb
ruby 2.4.3p205 (2017-12-14 revision 61247) [x86_64-darwin17]
Calculating -------------------------------------
String#=~ 1.088M (± 4.0%) i/s - 5.471M in 5.034404s
String#match? 5.138M (± 5.0%) i/s - 25.669M in 5.008810s
String#start_with? 6.314M (± 4.3%) i/s - 31.554M in 5.007207s
Comparison:
String#start_with?: 6314182.0 i/s
String#match?: 5138115.1 i/s - 1.23x slower
String#=~: 1088461.5 i/s - 5.80x slower
```
```
$ ruby -v code/string/end-string-checking-match-vs-end_with.rb
ruby 2.4.3p205 (2017-12-14 revision 61247) [x86_64-darwin17]
Calculating -------------------------------------
String#=~ 918.101k (± 6.0%) i/s - 4.650M in 5.084079s
String#match? 3.009M (± 6.8%) i/s - 14.991M in 5.005691s
String#end_with? 4.548M (± 9.3%) i/s - 22.684M in 5.034115s
Comparison:
String#end_with?: 4547871.0 i/s
String#match?: 3008554.5 i/s - 1.51x slower
String#=~: 918100.5 i/s - 4.95x slower
```
##### `String#start_with?` vs `String#[].==` [code](code/string/start_with-vs-substring-==.rb)
```
$ ruby -v code/string/end-string-checking-match-vs-end_with.rb
ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-darwin14]
Calculating -------------------------------------
String#start_with? 2.047M (± 4.5%) i/s - 10.242M in 5.015146s
String#[0, n] == 711.802k (± 7.3%) i/s - 3.551M in 5.019543s
String#[RANGE] == 651.751k (± 6.2%) i/s - 3.296M in 5.078772s
String#[0...n] == 427.207k (± 5.7%) i/s - 2.136M in 5.019245s
Comparison:
String#start_with?: 2046618.9 i/s
String#[0, n] ==: 711802.3 i/s - 2.88x slower
String#[RANGE] ==: 651751.2 i/s - 3.14x slower
String#[0...n] ==: 427206.8 i/s - 4.79x slower
```
##### `Regexp#===` vs `Regexp#match` vs `Regexp#match?` vs `String#match` vs `String#=~` vs `String#match?` [code ](code/string/===-vs-=~-vs-match.rb)
`String#match?` and `Regexp#match?` are available on Ruby 2.4 or later.
ActiveSupport [provides](http://guides.rubyonrails.org/v5.1/active_support_core_extensions.html#match-questionmark)
a forward compatible extension of `Regexp` for older Rubies without the speed
improvement.
> :warning:
> Sometimes you can't replace `match` with `match?`,
> This is only useful for cases where you are checking
> for a match and not using the resultant match object.
> :warning:
> `Regexp#===` is also faster than `String#match` but you need to switch the order of arguments.
```
$ ruby -v code/string/===-vs-=~-vs-match.rb
ruby 2.4.1p111 (2017-03-22 revision 58053) [x86_64-darwin16]
Calculating -------------------------------------
Regexp#match? 6.994M (± 3.0%) i/s - 35.144M in 5.029647s
String#match? 6.909M (± 3.3%) i/s - 34.663M in 5.023177s
String#=~ 2.784M (± 5.2%) i/s - 13.996M in 5.043168s
Regexp#=== 2.702M (± 4.5%) i/s - 13.631M in 5.056215s
Regexp#match 2.607M (± 4.9%) i/s - 13.025M in 5.009071s
String#match 2.362M (± 5.7%) i/s - 11.817M in 5.020344s
Comparison:
Regexp#match?: 6994107.7 i/s
String#match?: 6909055.7 i/s - same-ish: difference falls within error
String#=~: 2783577.8 i/s - 2.51x slower
Regexp#===: 2702030.0 i/s - 2.59x slower
Regexp#match: 2607484.0 i/s - 2.68x slower
String#match: 2362314.8 i/s - 2.96x slower
```
See [#59](https://github.com/fastruby/fast-ruby/pull/59) and [#62](https://github.com/fastruby/fast-ruby/pull/62) for discussions.
##### `String#gsub` vs `String#sub` vs `String#[]=` [code](code/string/gsub-vs-sub.rb)
```
$ ruby -v code/string/gsub-vs-sub.rb
ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-linux]
Warming up --------------------------------------
String#gsub 48.360k i/100ms
String#sub 45.739k i/100ms
String#dup["string"]= 59.896k i/100ms
Calculating -------------------------------------
String#gsub 647.666k (± 3.3%) i/s - 3.240M in 5.008504s
String#sub 756.665k (± 2.0%) i/s - 3.796M in 5.019235s
String#dup["string"]= 917.873k (± 1.8%) i/s - 4.612M in 5.026253s
Comparison:
String#dup["string"]=: 917873.1 i/s
String#sub: 756664.7 i/s - 1.21x slower
String#gsub: 647665.6 i/s - 1.42x slower
```
##### `String#gsub` vs `String#tr` [code](code/string/gsub-vs-tr.rb)
> [rails/rails#17257](https://github.com/rails/rails/pull/17257)
```
$ ruby -v code/string/gsub-vs-tr.rb
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-darwin14]
Calculating -------------------------------------
String#gsub 38.268k i/100ms
String#tr 83.210k i/100ms
-------------------------------------------------
String#gsub 516.604k (± 4.4%) i/s - 2.602M
String#tr 1.862M (± 4.0%) i/s - 9.320M
Comparison:
String#tr: 1861860.4 i/s
String#gsub: 516604.2 i/s - 3.60x slower
```
##### `String#gsub` vs `String#tr` vs `String#delete` [code](code/string/gsub-vs-tr-vs-delete.rb)
```
ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-linux]
Calculating -------------------------------------
String#gsub 1.342M (± 1.3%) i/s - 6.816M in 5.079675s
String#tr 2.627M (± 1.0%) i/s - 13.387M in 5.096083s
String#delete 2.924M (± 0.7%) i/s - 14.889M in 5.093070s
String#delete const 3.136M (± 2.6%) i/s - 15.866M in 5.064043s
Comparison:
String#delete const: 3135559.1 i/s
String#delete: 2923531.8 i/s - 1.07x slower
String#tr: 2627150.5 i/s - 1.19x slower
String#gsub: 1342013.4 i/s - 2.34x slower
```
##### `Mutable` vs `Immutable` [code](code/string/mutable_vs_immutable_strings.rb)
```
$ ruby -v code/string/mutable_vs_immutable_strings.rb
ruby 2.3.1p112 (2016-04-26 revision 54768) [x86_64-darwin14]
Calculating -------------------------------------
Without Freeze 7.279M (± 6.6%) i/s - 36.451M in 5.029785s
With Freeze 9.329M (± 7.9%) i/s - 46.370M in 5.001345s
Comparison:
With Freeze: 9329054.3 i/s
Without Freeze: 7279203.1 i/s - 1.28x slower
```
##### `String#sub!` vs `String#gsub!` vs `String#[]=` [code](code/string/sub!-vs-gsub!-vs-[]=.rb)
Note that `String#[]` will throw an `IndexError` when given string or regexp not matched.
```
$ ruby -v code/string/sub\!-vs-gsub\!-vs-\[\]\=.rb
ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-darwin14]
Calculating -------------------------------------
String#['string']= 74.512k i/100ms
String#sub!'string' 52.801k i/100ms
String#gsub!'string' 34.480k i/100ms
String#[/regexp/]= 55.325k i/100ms
String#sub!/regexp/ 45.770k i/100ms
String#gsub!/regexp/ 27.665k i/100ms
-------------------------------------------------
String#['string']= 1.215M (± 6.2%) i/s - 6.110M
String#sub!'string' 752.731k (± 6.2%) i/s - 3.749M
String#gsub!'string' 481.183k (± 4.4%) i/s - 2.414M
String#[/regexp/]= 840.615k (± 5.3%) i/s - 4.205M
String#sub!/regexp/ 663.075k (± 7.8%) i/s - 3.295M
String#gsub!/regexp/ 342.004k (± 7.5%) i/s - 1.715M
Comparison:
String#['string']=: 1214845.5 i/s
String#[/regexp/]=: 840615.2 i/s - 1.45x slower
String#sub!'string': 752731.4 i/s - 1.61x slower
String#sub!/regexp/: 663075.3 i/s - 1.83x slower
String#gsub!'string': 481183.5 i/s - 2.52x slower
String#gsub!/regexp/: 342003.8 i/s - 3.55x slower
```
##### `String#sub` vs `String#delete_prefix` [code](code/string/sub-vs-delete_prefix.rb)
[Ruby 2.5 introduced](https://bugs.ruby-lang.org/issues/12694) `String#delete_prefix`.
Note that this can only be used for removing characters from the start of a string.
```
$ ruby -v code/string/sub-vs-delete_prefix.rb
ruby 2.5.0p0 (2017-12-25 revision 61468) [x86_64-darwin17]
Calculating -------------------------------------
String#delete_prefix 4.112M (± 1.8%) i/s - 20.707M in 5.037928s
String#sub 814.725k (± 1.4%) i/s - 4.088M in 5.018962s
Comparison:
String#delete_prefix: 4111531.1 i/s
String#sub: 814725.3 i/s - 5.05x slower
```
##### `String#sub` vs `String#chomp` vs `String#delete_suffix` [code](code/string/sub-vs-chomp-vs-delete_suffix.rb)
[Ruby 2.5 introduced](https://bugs.ruby-lang.org/issues/13665) `String#delete_suffix`
as a counterpart to `delete_prefix`. The performance gain over `chomp` is
small and during some runs the difference falls within the error margin.
Note that this can only be used for removing characters from the end of a string.
```
$ ruby -v code/string/sub-vs-chomp-vs-delete_suffix.rb
ruby 2.5.0p0 (2017-12-25 revision 61468) [x86_64-darwin17]
Calculating -------------------------------------
String#sub 838.415k (± 1.7%) i/s - 4.214M in 5.027412s
String#chomp 3.951M (± 2.1%) i/s - 19.813M in 5.017089s
String#delete_suffix 4.202M (± 2.1%) i/s - 21.075M in 5.017429s
Comparison:
String#delete_suffix: 4202201.7 i/s
String#chomp: 3950921.9 i/s - 1.06x slower
String#sub: 838415.3 i/s - 5.01x slower
```
##### `String#unpack1` vs `String#unpack[0]` [code](code/string/unpack1-vs-unpack[0].rb)
[Ruby 2.4.0 introduced `unpack1`](https://bugs.ruby-lang.org/issues/12752) to skip creating the intermediate array object.
```
$ ruby -v code/string/unpack1-vs-unpack\[0\].rb
ruby 2.4.3p205 (2017-12-14 revision 61247) [x86_64-darwin17]
Warming up --------------------------------------
String#unpack1 224.291k i/100ms
String#unpack[0] 201.870k i/100ms
Calculating -------------------------------------
String#unpack1 4.864M (± 4.2%) i/s - 24.448M in 5.035203s
String#unpack[0] 3.778M (± 4.0%) i/s - 18.976M in 5.031253s
Comparison:
String#unpack1: 4864467.2 i/s
String#unpack[0]: 3777815.6 i/s - 1.29x slower
```
##### Remove extra spaces (or other contiguous characters) [code](code/string/remove-extra-spaces-or-other-chars.rb)
The code is tested against contiguous spaces but should work for other chars too.
```
$ ruby -v code/string/remove-extra-spaces-or-other-chars.rb
ruby 2.5.0p0 (2017-12-25 revision 61468) [x86_64-linux]
Warming up --------------------------------------
String#gsub/regex+/ 1.644k i/100ms
String#squeeze 24.681k i/100ms
Calculating -------------------------------------
String#gsub/regex+/ 14.668k (± 5.1%) i/s - 73.980k in 5.056887s
String#squeeze 372.910k (± 8.4%) i/s - 1.851M in 5.011881s
Comparison:
String#squeeze: 372910.3 i/s
String#gsub/regex+/: 14668.1 i/s - 25.42x slower
```
### Time
##### `Time.iso8601` vs `Time.parse` [code](code/time/iso8601-vs-parse.rb)
When expecting well-formatted data from e.g. an API, `iso8601` is faster and will raise an `ArgumentError` on malformed input.
```
$ ruby -v code/time/iso8601-vs-parse.rb
ruby 2.4.3p205 (2017-12-14 revision 61247) [x86_64-darwin17]
Warming up --------------------------------------
Time.iso8601 10.234k i/100ms
Time.parse 4.228k i/100ms
Calculating -------------------------------------
Time.iso8601 114.485k (± 3.5%) i/s - 573.104k in 5.012008s
Time.parse 43.711k (± 4.1%) i/s - 219.856k in 5.038349s
Comparison:
Time.iso8601: 114485.1 i/s
Time.parse: 43710.9 i/s - 2.62x slower
```
### Range
##### `cover?` vs `include?` [code](code/range/cover-vs-include.rb)
`cover?` only check if it is within the start and end, `include?` needs to traverse the whole range.
```
$ ruby -v code/range/cover-vs-include.rb
ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-linux]
Calculating -------------------------------------
range#cover? 85.467k i/100ms
range#include? 7.720k i/100ms
range#member? 7.783k i/100ms
plain compare 102.189k i/100ms
-------------------------------------------------
range#cover? 1.816M (± 5.6%) i/s - 9.060M
range#include? 83.344k (± 5.0%) i/s - 416.880k
range#member? 82.654k (± 5.0%) i/s - 412.499k
plain compare 2.581M (± 6.2%) i/s - 12.876M
Comparison:
plain compare: 2581211.8 i/s
range#cover?: 1816038.5 i/s - 1.42x slower
range#include?: 83343.9 i/s - 30.97x slower
range#member?: 82654.1 i/s - 31.23x slower
```
## Less idiomatic but with significant performance ruby
Checkout: https://github.com/fastruby/fast-ruby/wiki/Less-idiomatic-but-with-significant-performance-difference
## Submit New Entry
Please! [Edit this README.md](https://github.com/fastruby/fast-ruby/edit/main/README.md) then [Submit a Awesome Pull Request](https://github.com/fastruby/fast-ruby/pulls)!
## Something went wrong
Code example is wrong? :cry: Got better example? :heart_eyes: Excellent!
[Please open an issue](https://github.com/fastruby/fast-ruby/issues/new) or [Open a Pull Request](https://github.com/fastruby/fast-ruby/pulls) to fix it.
Thank you in advance! :wink: :beer:
## One more thing
[Share this with your #Rubyfriends! <3](https://twitter.com/intent/tweet?url=http%3A%2F%2Fgit.io%2F4U3xdw&text=Fast%20Ruby%20--%20Common%20Ruby%20Idioms%20inspired%20by%20%40sferik&original_referer=&via=juanitofatas&hashtags=#RubyFriends)
Brought to you by [@JuanitoFatas](https://twitter.com/juanitofatas)
Feel free to talk with me on Twitter! <3
## Also Checkout
- [Derailed Benchmarks](https://github.com/schneems/derailed_benchmarks)
Go faster, off the Rails - Benchmarks for your whole Rails app
- [Benchmarking Ruby](https://speakerdeck.com/davystevenson/benchmarking-ruby)
Talk by Davy Stevenson @ RubyConf 2014.
- [davy/benchmark-bigo](https://github.com/davy/benchmark-bigo)
Provides Big O notation benchmarking for Ruby.
- [The Ruby Challenge](https://therubychallenge.com/)
Talk by Prem Sichanugrist @ Ruby Kaigi 2014.
- [Fasterer](https://github.com/DamirSvrtan/fasterer)
Make your Rubies go faster with this command line tool.
## License
This work is licensed under a [Creative Commons Attribution-ShareAlike 4.0 International License](https://creativecommons.org/licenses/by-sa/4.0/).
## Code License
### CC0 1.0 Universal
To the extent possible under law, @JuanitoFatas has waived all copyright and related or neighboring rights to "fast-ruby".
This work belongs to the community.