gsub.rb

require 'benchmark/ips'

@alphabet = Range.new('a', 'z').to_a.join(',')

def slow
  @alphabet.gsub(',', '')
end

def fast
  @alphabet.delete(',')
end

Benchmark.ips do |x|
  x.report('slow') { slow }
  x.report('fast') { fast }
  x.compare!
end


Calculating -------------------------------------
                slow     9.820k i/100ms
                fast    65.006k i/100ms
-------------------------------------------------
                slow    105.372k (± 4.2%) i/s -    530.280k
                fast      1.068M (± 5.2%) i/s -      5.330M

Comparison:
                fast:  1068256.8 i/s
                slow:   105371.9 i/s - 10.14x slower