Ruby | Hash keep_if() function

Hash#keep_if() is a Hash class method which only keeps those key value pair that follows the block condition.

Syntax: Hash.keep_if()

Parameter: Hash values
block – condition

Return: key value pair that follows the block condition

Example #1 :

# Ruby code for Hash.keep_if() method

# declaring Hash value
a = {a:100, b:200}

# declaring Hash value
b = {a:100, c:300, b:200}

# declaring Hash value
c = {a:100}


# keep_if Value
puts "Hash a keep_if form : #{a.keep_if{|key| key != 100}}\n\n"

puts "Hash b keep_if form : #{b.keep_if{|key| key = 200}}\n\n"

puts "Hash c keep_if form : #{c.keep_if{|key| key != 200}}\n\n"

Output :

Hash a keep_if form : {:a=>100, :b=>200}

Hash b keep_if form : {:a=>100, :c=>300, :b=>200}

Hash c keep_if form : {:a=>100}

Example #2 :

# Ruby code for Hash.keep_if() method

# declaring Hash value
a = { "a" => 100, "b" => 200 }

# declaring Hash value
b = {"a" => 100}

# declaring Hash value
c = {"a" => 100, "c" => 300, "b" => 200}

# keep_if Value
puts "Hash a keep_if form : #{a.keep_if{|key| key != 100}}\n\n"

puts "Hash b keep_if form : #{b.keep_if{|key| key = 200}}\n\n"

puts "Hash c keep_if form : #{c.keep_if{|value| value != 200}}\n\n"

Output :

Hash a keep_if form : {"a"=>100, "b"=>200}

Hash b keep_if form : {"a"=>100}

Hash c keep_if form : {"a"=>100, "c"=>300, "b"=>200}