compare between first, range and active_supports truncate

ruby_truncate_vs_first_vs_range.rb

require 'benchmark/ips'
require 'active_support/all'

STRING = 'Once upon a time in a world far far away'

def use_truncate
  STRING.truncate(27)
end

def use_first
  STRING.first(27)
end

def use_range
  STRING[0...27]
end

Benchmark.ips do |x|
  x.report('truncate') { use_truncate }
  x.report('first') { use_first }
  x.report('range') { use_range }
  x.compare!
end

=begin
Warming up --------------------------------------
            truncate    53.883k i/100ms
               first    78.153k i/100ms
               range    99.488k i/100ms
Calculating -------------------------------------
            truncate    760.175k (± 5.5%) i/s -      3.826M in   5.049342s
               first      1.162M (±12.1%) i/s -      5.705M in   5.038751s
               range      1.719M (± 6.5%) i/s -      8.556M in   5.001056s

Comparison:
               range:  1718907.6 i/s
               first:  1162328.6 i/s - 1.48x  slower
            truncate:   760175.0 i/s - 2.26x  slower
=end