Add Single And Double Quoted String Notation as a ruby til

Author: jbranchaud

README.md

@@ -9,7 +9,7 @@ and pairing with smart people at Hashrocket.
 
 For a steady stream of TILs, [sign up for my newsletter](https://tinyletter.com/jbranchaud).
 
-_865 TILs and counting..._
+_866 TILs and counting..._
 
 ---
 
@@ -706,6 +706,7 @@ _865 TILs and counting..._
 - [Set RVM Default Ruby](ruby/set-rvm-default-ruby.md)
 - [Show Public Methods With Pry](ruby/show-public-methods-with-pry.md)
 - [Silence The Output Of A Ruby Statement In Pry](ruby/silence-the-output-of-a-ruby-statement-in-pry.md)
+- [Single And Double Quoted String Notation](ruby/single-and-double-quoted-string-notation.md)
 - [Squeeze Out The Extra Space](ruby/squeeze-out-the-extra-space.md)
 - [String Interpolation With Instance Variables](ruby/string-interpolation-with-instance-variables.md)
 - [Summing Collections](ruby/summing-collections.md)

ruby/single-and-double-quoted-string-notation.md

@@ -0,0 +1,38 @@
+# Single And Double Quoted String Notation
+
+If you are building a string that involves interpolation and literal double
+quotes, then you'll have to do some escaping. Here is an example:
+
+```ruby
+> feet, inches = [6, 4]
+> puts "I am #{feet}'#{inches}\" tall"
+I am 6'4" tall
+```
+
+Having to escape a single instance of a double quote isn't so bad. If you find
+yourself having to do it a bunch, Ruby has something for you. It is a string
+syntax feature called [Percent Notation](percent-notation.md).
+
+You can use percent notation to define double-quoted strings using `Q`:
+
+```ruby
+> puts %Q[I am #{feet}'#{inches}" tall]
+I am 6'4" tall
+```
+
+No need to escape the double quote here.
+
+There is a single-quoted version as well using `q`:
+
+```ruby
+> puts %q[I am #{feet}'#{inches}\" tall]
+I am #{feet}'#{inches}\" tall
+```
+
+This is notably less useful than `%Q`. For that reason, `%Q` makes sense as a
+default and it makes up the percent notations unmodified behavior:
+
+```ruby
+> puts %[I am #{feet}'#{inches}" tall]
+I am 6'4" tall
+```