Ruby Hash compare_by_identity () 函数

Hash#compare_by_identity()是一个Hash类方法，它将哈希键与它的身份进行比较，并将完全相同的对象视为相同的键。

语法。Hash.compare_by_identity ()

参数：哈希数组

返回：比较哈希键和它的身份。

例子 #1 :

# Ruby code for compare_by_identity () method
  
# declaring Hash value
a = {a:100, b:nil}
  
# declaring Hash value
b = {a:100, c:nil, b:"b"}
  
# declaring Hash value
c = {a:100}
  
puts "compare_by_identity  a : #{a.compare_by_identity}\n\n"
  
puts "compare_by_identity  b : #{b.compare_by_identity}\n\n"
  
puts "compare_by_identity  b : #{c.compare_by_identity}\n\n"

输出:

compare_by_identity  a : {:a=>100, :b=>nil}

compare_by_identity  b : {:a=>100, :c=>nil, :b=>"b"}

compare_by_identity  b : {:a=>100}

例子 #2 :

# Ruby code for compare_by_identity () method
  
# declaring Hash value
a = { "a" => 100, "b" => 200 }
  
# declaring Hash value
b = {"a" => 100}
  
# declaring Hash value
c = {"a" => 100, "c" => "c", "b" => 200}
  
puts "compare_by_identity  a : #{a.compare_by_identity}\n\n"
  
puts "compare_by_identity  b : #{b.compare_by_identity}\n\n"
  
puts "compare_by_identity  b : #{c.compare_by_identity}\n\n"

输出:

compare_by_identity  a : {"a"=>100, "b"=>200}

compare_by_identity  b : {"a"=>100}

compare_by_identity  b : {"a"=>100, "c"=>"c", "b"=>200}