Add Use Rescue As Part Of Inline Statement as a Ruby TIL

ruby/use-rescue-as-part-of-inline-statement.md

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+# Use Rescue As Part Of Inline Statement
+
+In Ruby I typically think of `rescue` as block syntax that I can use to handle
+exceptions.
+
+```ruby
+begin
+  User.update!(password:)
+rescue
+  puts "There was an issue updating the password"
+end
+```
+
+The `rescue` keyword can also be used as part of an inline statement as a way of
+providing a _fallback_ value when the first part of the statement raises.
+
+For instance, if I'm trying to access some value on an array that happens to be
+`nil`, it is going to raise:
+
+```ruby
+> scores.first
+(irb):7:in '<main>': undefined method 'first' for nil (NoMethodError)
+```
+
+I can instead tack on a `rescue 0` which will give it `0` as a fallback value:
+
+```ruby
+> scores.first rescue 0
+=> 0
+```
+
+Of course, there are more idiomatic ways to handle this kind of situation in
+Ruby. Maybe something like this:
+
+```ruby
+> Array(scores).first || 0
+=> 0
+```
+
+Another way I've seen this inline rescue used is to print out the exception
+caused by that line of code, using `$!` (the global variable for the most
+recently raised exception).
+
+```ruby
+> scores.first rescue puts $!
+undefined method 'first' for nil
+=> nil
+```
+
+That is a one-liner for the following:
+
+```ruby
+begin
+  scores.first
+rescue => e
+  puts e
+end
+```
+
+The big caveat that goes with this is the same one that goes with any other
+blanket `rescue` block. If you are indiscriminately rescuing exceptions without
+being intentional about what you are rescuing and why, you could be potentially
+burying exceptions that you need to know about.