Ruby | Hash reject! method

Hash#reject!() is a Hash class method which checks whether any changes are made in the hash array or not

Syntax: Hash.reject!()

Parameter: Hash values

Return: true – if changes are made otherwise return false

Example #1 :

# Ruby code for Hash.reject!() 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}


# reject! Value
puts "Hash a reject! form : #{a.reject! {|key, value| key < "b"}}\n\n"

Output :

Hash a reject! form : {"b"=>200}

Example #2 :

# Ruby code for Hash.reject!() method

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

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


# reject! Value

puts "Hash b reject! form : #{b.reject!{|key, value| value < 200}}\n\n"

puts "Hash c reject! form : #{c.reject!{|key, value| key < "b"}}\n\n"

Output :

Hash b reject! form : {}

Hash c reject! form : {"c"=>300, "b"=>200}