3.13.0

CHANGES:

• Support module%ppx syntax (@anmonteiro,
  #2771)
• Extend open to arbitrary module expression (@anmonteiro,
  #2773)
• Wrap let lazy patterns = .. in parentheses (let lazy(patterns) = ..)
  (@anmonteiro, #2774)
• Print poly variants as normal variansts (@sander Spies,
  #2708)
• Improve printing of anonymous function return type (@sander Spies,
  #2686)
• Improve printing of destructuring with local open (@sander Spies,
  #2684).
• Parse and print attributes in binding let ops (@anmonteiro,
  #2777).
• Parse polymorphic variants starting with [| (@anmonteiro,
  #2781)
• Always add a line break in records with 2 or more fields (@anmonteiro,
  #2779)
• Always break nonempty doc comments after */ (@anmonteiro,
  #2780)
• Improve printing of arrows with labelled arguments (@anmonteiro,
  #2778)
• Parse and print extensions in open%foo expressions and structure items
  (@anmonteiro, #2784)
• Add support for module type substitutions
  (@anmonteiro, #2785)
• Support type%foo extension sugar syntax (@anmonteiro,
  #2790)
• Support quoted extensions (@anmonteiro,
  #2794)
• Parse universal type variables in signature items (@anmonteiro,
  #2797)
• Fix formatting of callbacks with sequence expressions (@anmonteiro,
  #2799)
• Fix printing of attributes on module expressions (@anmonteiro,
  #2803)