anchor.diff:  
   |'\f'
   |formfeed
  +
  +|'\\'
  +|backslash
  +
  +|'\''
  +|single quote (for single quoted and triple single quoted strings)
  +
  +|'\"'
  +|double quote (for double quoted and triple double quoted strings)
   |====
   
   ==== Unicode escape sequence
  
positive.code: include::{projectdir}/src/spec/test/SyntaxTest.groovy[tags=triple_double_1,indent=0]
  ----
  
  
  === Slashy string
  === Dollar slashy string
  
negative.code: 
  NOTE: Double quoted strings are plain +java.lang.String+ if there's no interpolated expression, 
  but are +groovy.lang.GString+ instances if interpolation is present.
  
  NOTE: To escape a double quote, you can use the backslash character: +"A double quote: \""+.
  
  ==== String interpolation
  
  