Methods Frequently Asked in Ruby Silver Exam

Here is a summary of methods frequently asked in the Ruby Silver exam. Reference

concat(Array)

array.concat(other_array)

The concat method appends the elements of other_array to the end of array. It is a destructive method that modifies the receiver itself. The return value is the receiver itself.

fruits = ["apple", "orange", "banana"]
fruits.concat(["kiwi", "strawberry"])
p fruits
# Output: ["apple", "orange", "banana", "kiwi", "strawberry"]

This is a destructive method.

concat(String)

str.concat(other_str)

str.concat(integer)

The concat method is an alias for <<. It appends other_str to the end of str. If an integer is specified, it appends the corresponding character code as a single character to the end of str.

s = "Hello"
s.concat(", world")
puts s
# Output: Hello, world

The fact that it is an alias for << is a common exam question.

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