How to Use the merge Method in Ruby
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Contents
In this article, you will learn how to use the merge method in Ruby.
The merge Method
In Ruby, the merge method is used to combine two hashes into a new hash. Here is an example of how to use the merge method:
hash1 = { a: 1, b: 2 }
hash2 = { c: 3, d: 4 }
merged_hash = hash1.merge(hash2)
puts merged_hash #=> { a: 1, b: 2, c: 3, d: 4 }
In the example above, the merge method is called on hash1, and hash2 is passed as an argument. The result of the merge is stored in the variable merged_hash. The resulting hash contains all the key-value pairs from both hash1 and hash2.
If there are key-value pairs in both hash1 and hash2 that have the same key, the value from hash2 will overwrite the value from hash1 in the resulting hash. You can also pass a block to the merge method to specify how conflicting values should be handled.
Here is an example of using a block with merge:
hash1 = { a: 1, b: 2 }
hash2 = { b: 3, c: 4 }
merged_hash = hash1.merge(hash2) { |key, old_val, new_val| old_val + new_val }
puts merged_hash #=> { a: 1, b: 5, c: 4 }
In the example above, there is a conflict for the key :b between hash1 and hash2. The block passed to merge specifies that conflicting values should be added together. The resulting hash has a value of 5 for the key :b.