How to Copy a Map in Ruby - Step by Step Examples

How to Copy a Map in Ruby ?

Answer

To copy a hash in Ruby, you can use the `dup` method, the `clone` method, or the `merge` method to create a new hash with the same key-value pairs as the original hash. These methods provide straightforward ways to duplicate a hash.

✐ Examples

1 Copying a Hash Using the dup Method

We can copy a hash in Ruby using the `dup` method, which creates a new hash with the same key-value pairs as the original hash.

For example,

We start by declaring and initializing a hash named original_hash with some key-value pairs. In this example, the hash has string keys and integer values.
We use the dup method to create a new hash named copied_hash that contains the same key-value pairs as original_hash.
We print the copied hash to the console using the puts function to verify the copy.

Ruby Program

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

# Copy the hash using the dup method
copied_hash = original_hash.dup

# Print the copied hash
puts "Copied Hash: #{copied_hash}"

Output

Copied Hash: {"one"=>1, "two"=>2, "three"=>3}

2 Copying a Hash Using the clone Method

We can also copy a hash in Ruby using the `clone` method, which creates a new hash with the same key-value pairs as the original hash.

For example,

We start by declaring and initializing a hash named original_hash with some key-value pairs. In this example, the hash has string keys and integer values.
We use the clone method to create a new hash named copied_hash that contains the same key-value pairs as original_hash.
We print the copied hash to the console using the puts function to verify the copy.

Ruby Program

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

# Copy the hash using the clone method
copied_hash = original_hash.clone

# Print the copied hash
puts "Copied Hash: #{copied_hash}"

Output

Copied Hash: {"one"=>1, "two"=>2, "three"=>3}

3 Copying a Hash Using the merge Method

We can copy a hash in Ruby using the `merge` method to add all key-value pairs from the original hash to a new hash.

For example,

We start by declaring and initializing a hash named original_hash with some key-value pairs. In this example, the hash has string keys and integer values.
We declare an empty hash named copied_hash.
We use the merge method to add all key-value pairs from original_hash to copied_hash.
We print the copied hash to the console using the puts function to verify the copy.

Ruby Program

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

# Copy the hash using the merge method
copied_hash = {}.merge(original_hash)

# Print the copied hash
puts "Copied Hash: #{copied_hash}"

Output

Copied Hash: {"one"=>1, "two"=>2, "three"=>3}

Summary

In this tutorial, we learned How to Copy a Map in Ruby language with well detailed examples.

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How to Copy a Map in Ruby - Step by Step Examples