Man, I hope you don't use grep very often (by default it uses exit code 1 when it doesn't find anything).
In the former, if a result can't be found it will return `nil` but in the latter it expects the record to exist and so will raise an exception if it can't be found.
IMO returning nil instead of an exception for the above is practical for me. Much easier to work with.
Having `find(4)` raising an exception is because you'll typical use it in your member actions for a controller where it's reasonable to want an exception if something can't be found.
It's just Rails being Rails (practical sometimes at the expense of possible interpretation of correctness). You do have to retain stuff like this in your head, but it becomes habit pretty quickly.
I've have found `find_by!` useful though. Say you want to raise an exception with `find_by!(email: "asd@asd.com")` or `find_by!(slug: "parameterized-string")` etc.
echo foo | grep bar | cat
echo foo | grep bar || true echo foo | grep bar || :Not to mention tar which is just impossible to get right on the first try.