delete_multiple_characters.rb

require 'benchmark'

TIMES = 1_000_000

s = "a string"

Benchmark.bmbm do |x|
  x.report("delete") do
    TIMES.times { s.delete("rin") }
  end

  x.report("multiple delete") do
    TIMES.times { s.delete("r").delete("i").delete("n") }
  end

  x.report("tr") do
    TIMES.times { s.tr("rin", "") }
  end

  x.report("gsub with regexp") do
    TIMES.times { s.gsub(/[rin]/, "") }
  end
end

# Rehearsal ----------------------------------------------------
# delete             2.030000   0.010000   2.040000 (  2.028561)
# multiple delete    5.710000   0.010000   5.720000 (  5.718976)
# tr                 2.380000   0.000000   2.380000 (  2.376503)
# gsub with regexp   5.780000   0.020000   5.800000 (  5.810256)
# ------------------------------------------ total: 15.940000sec

#                        user     system      total        real
# delete             2.030000   0.000000   2.030000 (  2.026632)
# multiple delete    5.730000   0.010000   5.740000 (  5.739280)
# tr                 2.390000   0.000000   2.390000 (  2.388175)
# gsub with regexp   5.820000   0.010000   5.830000 (  5.836098)