LunarML   

A standard ML compiler that produces Lua / JavaScript.

---

     

---

Features

• Most of SML '97 language + Signatures + Functors
• A subset of the SML Basis Library
• An Interface to Lua
• ML Basis system like MLton

Successor ML Features

• Monomorphic non-exhaustive bindings

• Simplified recursive value bindings

  SML '97-compatible ordering for
  type variables is also supported:

  val <tyvarseq> rec <valbind>

• Abstype as derived form

• Fixed manifest type specifications

• Abolish sequenced type realizations

• Line comments

• Extended literal syntax

  • Underscores
    • 3.1415_9265
    • 0xffff_ffff
  • Binary notation
    • 0wb
    • 0b
  • Eight hex digits in text
    • \Uxxxxxxxx

• Record punning

• Record extension

• Record update

• Conjunctive patterns

• Disjunctive patterns

• Nested matches

• Pattern guards

• Optional bars and semicolons

• Optional else branch

• Do declarations

• With type in signatures

Planned Extensions

• Vector expressions and patterns

• Packaged modules

  • Alice ML
  • HaMLet S

• Hexadecimal floating-point constants

  Examples

  • 0x1.ffff_ffff_ffff_f
  • 0x1p1024

  
  

  Syntax

  <hexadecimal-integer-constant> ::= '~'? '0' 'w'? 'x' <hexadecimal-digit-sequence>

  <hexadecimal-floating-point-constant> ::= '~'? '0x' <hexadecimal-digit-sequence> (<binary-exponent-part> | 

  '.' <hexadecimal-digit-sequence> <binary-exponent-part>?)

  <hexadecimal-digit-sequence> ::= <hexadecimal-digit> ('_'* <hexadecimal-digit>)*

  <binary-exponent-part> ::= [pP] '~'? <digit> ('_'* <digit>)?

  
  

  In Short

  The ( binary ) exponent part is optional and
  tilde ( ~ ) is used for the negation symbol.

• Variably-encoded Unicode escape sequence in string literals

  Examples

  • \u{3042}

  
  

  Details

  The \u{} escape sequence makes it possible to
  embed unicode scalar values in a string literals.

  The compiler encodes the character in
  UTF-8,16,32 depending on the string type.