Elixir 1.3 was released at the end of June. Personally and professionally, the upgrade went smoothly without any hiccups. However, upgrading caused deprecation warnings to pop up when running my tests or starting my server.
The deprecation warning looked a little like this:
The awesome part about this deprecation warning is that it is really straight forward about how to fix it. Moreover, reading the release notes gives a great background about why this deprecation warning exists.
The code that I needed to refactor that caused this warning looked a little bit like this:
The code looks at the JSON from my request and sanitizes it so that it can be
nicely inserted into the database later on. The problem with this code (and why Elixir 1.3 has
a deprecation warning about it), is that it implicitly changes the value of
inside of the if block and
my_params is being accessed outside of this scope.
This is not very functional and can lead to unintended consequences.
To fix this, Elixir prefers that I explicitly return the variable that is changing so that it can be safely used outside of the scope.
The fix code is below:
Now, I am explicitly setting the variable
my_params that I was previously changing inside of
the if block. If
my_params["links"] does not exist (is
nil), I will return the initial value.
my_params["links"] does exist, it will return
links. Now both cases
are explicitly laid out in the code.
This change makes updating the variable safer and, in my opinion, makes the code more readable and more explicit.