Pattern Matching

Creating a function that declares a parameter twice in order to check if two different passed-in parameters are identical is not something I would have thought of.

Drives home the point that pattern matching within a function is the same pattern matching used to select the function to run.

Notes

1. All values on the left-hand side of a pattern match are unbound before the match is made.

2. Avoid this by using the pin (^) operator.

Exercises

1. Write a function that takes a two-element tuple parameter and uses pattern matching to return a two-element tuple with the elements swapped.

   defmodule Patterns do
     def swap({a, b}) do
       {b, a}
     end
   end
   
   Patterns.swap({1, 2})
   
   {2, 1}

2. Write a function that takes two parameters and returns true if they are the same. Use pattern matching and not conditional logic. All notes and comments are my own opinion. Follow me at @rgacote@genserver.social