P.S: The python backend is broken.

The Syntax rules of JML could be found at Parser.jl. Not all valid syntax constructs are implemented in the compiler yet. Type checker is WIP.

• infix operators with custom associativities and precendences:

      infix add 5
      infix cons 2 right
  

• pure lexical scope, and distinguish let-in bindings from let rec - in bindings.

• FFI via foreign keyword

      foreign Base
      def p = Base.getproperty
  

• provide accurate source code positions when reporting errors

• match expression

• type inference with type classes

• parameterised modules

Press \ to enter jml mode.

julia> \
jml>

• Str := value=str
• Nil := ["()"]
• Bind := [name=id %get_str, '=', value=Exp]
• Let := [loc=:let %get_loc, rec=:rec.? % maybe_to_bool, ...
• Fun := [loc=:fn %get_loc, "(", args=join_rule(",", ...
• Match := [loc=:match %get_loc, sc=Exp, :with,
• If := [loc=:if %get_loc, cond=Exp, :then, ...
• Num := [neg="-".? % maybe_to_bool, (int=integer) | (float=float)]
• Boolean := value=("true" | "false")
• NestedExpr = ['(', value=Exp, ')'] => _.value
• Var := value=id %get_str
• Block := [loc='{' %get_loc, stmts=Stmt{*}, '}']]
• Atom = Nil | NestedExpr | Num | Str | Boolean | Var | List
• Attr := [value=Atom, attrs=(['.', id % get_str] % second){*}]
• Call := [fn=Attr, ['(', args = join_rule(",", Attr), ')'].?]
• List := [loc='[', elts=join_rule(',', Exp), ']']
• Comp = Call | Let | Fun | Match | If | Block
• Op := ...
• Top := [hd=Comp, tl=[Op, Comp]{*}]
• Custom := [value=Exp, [',', next=Custom].?] | [kw=id, value=Exp, [',', next=Custom].?]
• Exp := [top=Top, [do_custom::Bool='{' => true, [custom=Custom].?, '}'].?]
• Define := [loc=:def %get_loc, name=id_str, '=', value=Exp]
• Infix := [loc=:infix %get_loc, name=id_str, prec=integer %get_str, is_right="right".? % maybe_to_bool]
• Foreign := [loc=:foreign %get_loc, paths=join_rule('.', id_str)]
• Import := [loc=:import %get_loc, is_qual=:qualified.? %maybe_to_bool, paths=join_rule('.', id_str)]
• Ops := [loc=:export %get_loc, names=id_str{*}]
• Stmt = [Exp | Import | Module, ';'.?] % first
• TopStmt = Define | Import | Infix | Stmt | Foreign | Ops
• [?] Module := [loc=:module %get_loc, name=id_str, params=id_str{*}, :where, stmts=TopStmt{*}, :end.?]