Ruby | Array class index() function

index() is an Array class method which returns the index of the first object in the array.

Syntax: Array.index()

Parameter: Array
obj – object to search for

Return: Index value of the first array

Example #1 :

# Ruby code for index() method

# declaring array
a = [18, 22, 33, nil, 5, 6]

# declaring array
b = [1, 4, 1, 1, 88, 9]

# declaring array
c = [18, 22, nil, nil, 50, 6]

# index
puts "index : #{a.index(5)}\n\n"

# index
puts "index : #{b.index(4)}\n\n"

# index
puts "index : #{c.index(nil)}\n\n"

Output :

index : 4

index : 1

index : 2

Example #2 :

# Ruby code for index() method

# declaring array
a = ["abc", "nil", "dog"]

# declaring array
b = ["cow", nil, "dog"]

# declaring array
c = ["cat", nil, nil]

# index
puts "index : #{a.index("abc")}\n\n"

# index
puts "index : #{b.index(nil)}\n\n"

# index
puts "index : #{c.index(nil)}\n\n"

Output :

index : 0

index : 1

index : 1