Ruby | Enumerable none?() function

The none?() of enumerable is an inbuilt method in Ruby returns a boolean value true if none of the objects in the enumerable satisfies the given condition, else it returns false. It compares all the elements with the pattern and returns true if none of them matches with the pattern.

Syntax enu.none? { |obj| block } or enu.none?(pattern)

Parameters: The function takes two types of parameters, one is the object and the block, while the other is the pattern. In case nothing is passed, it assumes to be default object and block which returns true if none of the objects are true or nil.

Return Value: It returns a boolean value.

Example #1:

# Ruby program for none? method in Enumerable

# Initialize an enumerable
enu1 = [10, 19, 18]

# checks if all numbers are greater
# than 4 or not
res1 = enu1.none? { |num| num>4}

# prints the result
puts res1


# checks if all numbers are greater
# than 4 or not
res2 = enu1.none? { |num| num>=20}

# prints the result
puts res2

Output:

false
true

Example #2:

# Ruby program for none? method in Enumerable

# Initialize an enumerable
enu1 = [10, 19, 20]

# Checks
res1 = enu1.none?(Numeric)

# prints the result
puts res1

# Initialize
enu2 = [nil, nil]

# Checks
res2 = enu2.none?
# prints the result
puts res2

Output:

false
true