Ruby attr_accessor vs. Getter / Setter-Benchmark: Warum ist Accessor schneller?
Ich habe gerade attr_accessor gegen äquivalente Getter / Setter-Methoden getestet:
class A
# we define two R/W attributes with accessors
attr_accessor :acc, :bcc
# we define two attributes with getter/setter-functions
def dirA=(d); @dirA=d; end
def dirA; @dirA; end
def dirB=(d); @dirB=d; end
def dirB; @dirB; end
end
varA = A.new
startT = 0
dirT = 0
accT = 0
# now we do 100 times the same benchmarking
# where we do the same assignment operation
# 50000 times
100.times do
startT = Time.now.to_f
50000.times do |i|
varA.dirA = i
varA.dirB = varA.dirA
end
dirT += (Time.now.to_f - startT)
startT = Time.now.to_f
50000.times do |i|
varA.acc = i
varA.bcc = varA.acc
end
accT += (Time.now.to_f - startT)
end
puts "direct: %10.4fs" % (dirT/100)
puts "accessor: %10.4fs" % (accT/100)
Programmausgabe ist:
direct: 0.2640s
accessor: 0.1927s
Also dieattr_accessor
ist deutlich schneller. Könnte jemand bitte einige Weisheiten teilen, warum das so ist?