Ruby Hash compact()函数

compact()是一个Hash类的方法，它在删除Hash中的所有 “nil “值元素（如果有的话）后返回Hash。

语法。Hash.compact()

参数：要去除’nil’值的Hash。

返回：从Hash中删除所有的 “nil “值。

例子 #1:

# Ruby code for compact() method
# showing how to remove nil values
  
  
# declaring Hash value
a = {a:100, b:nil}
  
# declaring Hash value
b = {a:100, c:nil, b:200}
  
# declaring Hash value
c = {a:100}
  
  
# removing nil value from Hash
puts "removing nil value : #{a.compact}\n\n"
  
# removing nil value from Hash
puts "removing nil value : #{b.compact}\n\n"
  
# removing nil value from Hash
puts "removing nil value : #{c.compact}\n\n"

输出:

removing nil value : {a:100}

removing nil value : {a:100, b:200}

removing nil value : {a:100}

例子#2。

# Ruby code for compact() method
# showing how to remove nil values
  
# declaring Hash value
a = { "a" => nil, "b" => 200 }
  
# declaring Hash value
b = {"a" => 100}
  
# declaring Hash value
c = {"a" => 100, "c" => nil, "b" => 200}
  
# removing nil value from Hash
puts "removing nil value : #{a.compact}\n\n"
  
# removing nil value from Hash
puts "removing nil value : #{b.compact}\n\n"
  
# removing nil value from Hash
puts "removing nil value : #{c.compact}\n\n"

输出:

removing nil value : {b:200}

removing nil value : {a:100}

removing nil value : {a:100, b:200}