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When to use the map method in Ruby?
Map is a Ruby method that you can use with Arrays, Hashes & Ranges. The main use for map is to TRANSFORM data. For example: Given an array of strings, you could go over every string & make every character UPPERCASE.
How to change values in a hash in Ruby?
Ruby 2.4 introduced the method Hash#transform_values!, which you could use. Less code and clear intent. Also faster because no new objects are allocated beyond the values that must be changed. A bit more readable one, map it to an array of single-element hashes and reduce that with merge
How to serialize a hash to an XML string?
I’ve just made this “serialization” module in Ruby that takes a hash and outputs a XML string. I’ve used #map and some recursion. How could that be improved?
When to use the with _ index method in Ruby?
If you need an index with your values you can use the with_index method. You can pass a parameter to with_index if you don’t want to start from index 0. You can use a shorthand version for map when you’re calling a method that doesn’t need any arguments.
When to use array and range in Ruby?
In English dictionary, array means collection. In Ruby also, it is a collection. But before starting to learn about arrays, first you should know their use. It is very useful to store data when they are large in number. Imagine that you have to make a software for a firm and they have to store the price of 100 different products.
Which is the exclusive range operator in Ruby?
So in the above example, the array contains fixnum, float and string also. .. and ( double dot and triple dot ) are range operators in Ruby. These operators generate a sequence of numbers or characters given to them. (..) is the inclusive and (…) is the exclusive range operator.
What’s the maximum number that can be in the range in Ruby?
The maximum value in (1..5) is 5 ( as it includes 5 also ) and the minimum value is 1. One more important operator is ===. It is used to check whether a number lies in the range or not. It returns true if the number is in the range else false.