gistfile1

require 'benchmark'
require 'benchmark/ips'

other = "test"

n = 100_000

Benchmark.ips do |x|
  x.report('#{...}') { n.times { "test #{other} test" } }
  x.report('#<<') { n.times { "test " << other << " test" } }
  x.report('#+') { n.times { "test " + other + " test" } }
end

# $ ruby string_test.rb
# Calculating -------------------------------------
#               #{...}         1 i/100ms
#                  #<<         1 i/100ms
#                   #+         1 i/100ms
# -------------------------------------------------
#               #{...}        6.4 (±31.2%) i/s -         30 in   5.039693s
#                  #<<        7.8 (±12.8%) i/s -         38 in   5.026323s
#                   #+        5.9 (±16.9%) i/s -         29 in   5.050913s