Add Block Syntaxes Have Different Precedence as a Ruby TIL

ruby/block-syntaxes-have-different-precedence.md

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+# Block Syntaxes Have Different Precedence
+
+There are two syntaxes for defining a block in Ruby. The semantically shorthand
+syntax uses the curly braces (`{}`). The semantically multi-line syntax uses
+`do` and `end`. For nearly all intents and purposes they are interchangable.
+
+It is, however, worth noting that the `do`/`end` version has a lower precedence
+than the already low precedence of `{}`. That said, you have to write some
+weird code for this to become an issue.
+
+Let's say we have two methods, `method_one` and `method_two`. They are both
+called on the same line like below and then followed by a block argument. Which
+method receives the block argument?
+
+```ruby
+method_one method_two { |n|
+  puts "Executing a block: #{n}"
+}
+
+method_one method_two do |n|
+  puts "Executing a block: #{n}"
+end
+```
+
+In the first case, with the curly braces, `method_two` receives the block as an
+argument. In the second case, with the `do`/`end`, `method_one` receives the
+block as an argument.
+
+[source](http://localhost:3131/ruby-operators/curly-braces#block-shorthand)