ror零碎

instance_of?  父类为false

is_a? 父类为true

 

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taint 

o ={:name=>"china"}
o.taint
o1={:subName=>"c"}

o11={:subSubName=>"c11"}

o1[:sub]=o11

o[:sub]=o1

oo=o.dup


p o[:sub].tainted? #false
p oo.tainted?        #true

 

 

str1="str"


str2=str1.dup

str1.taint

p   str2.tainted? #false