How to Check if a Map is Empty in Ruby - Step by Step Examples

How to Check if a Map is Empty in Ruby ?

Answer

To check if a hash is empty in Ruby, you can use the empty? method. This method returns a boolean value indicating whether the hash contains any elements.

✐ Examples

1 Checking if a Hash is Empty Using empty? Method

We can check if a hash is empty in Ruby using the empty? method, which returns true if the hash contains no elements and false otherwise.

For example,

We start by declaring and initializing an empty hash named my_map. In this example, the hash has string keys and integer values.
We use the empty? method to check if the hash is empty. The empty? method returns a boolean value indicating whether the hash contains any elements.
We print the result to the console using the puts function.

Ruby Program

my_map = {}

# Check if the hash is empty using empty? method
is_empty = my_map.empty?

# Print the result
puts "Is the hash empty? #{is_empty}"

Output

Is the hash empty? true

2 Checking if a Non-Empty Hash is Empty Using empty? Method

We can check if a non-empty hash is empty in Ruby using the empty? method, which returns false if the hash contains elements.

For example,

We start by declaring and initializing a hash named my_map with some key-value pairs. In this example, the hash has string keys and integer values.
We use the empty? method to check if the hash is empty. The empty? method returns a boolean value indicating whether the hash contains any elements.
We print the result to the console using the puts function.

Ruby Program

my_map = {
    'one' => 1,
    'two' => 2,
    'three' => 3
}

# Check if the hash is empty using empty? method
is_empty = my_map.empty?

# Print the result
puts "Is the hash empty? #{is_empty}"

Output

Is the hash empty? false

3 Checking if a Hash is Empty After Clearing Using empty? Method

We can check if a hash is empty in Ruby after clearing its elements using the empty? method, which returns true if the hash contains no elements.

For example,

We start by declaring and initializing a hash named my_map with some key-value pairs. In this example, the hash has string keys and integer values.
We use the clear method to remove all elements from the hash, making it empty.
We use the empty? method to check if the hash is empty after clearing. The empty? method returns a boolean value indicating whether the hash contains any elements.
We print the result to the console using the puts function.

Ruby Program

my_map = {
    'one' => 1,
    'two' => 2,
    'three' => 3
}

# Clear the hash
my_map.clear

# Check if the hash is empty using empty? method
is_empty = my_map.empty?

# Print the result
puts "Is the hash empty? #{is_empty}"

Output

Is the hash empty? true

Summary

In this tutorial, we learned How to Check if a Map is Empty in Ruby language with well detailed examples.

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How to Check if a Map is Empty in Ruby - Step by Step Examples