Notational conventions used in the grammar

• Each syntax class is defined by a list of alternatives, one alternative on each line. An empty phrase is represented by an empty line.
• The brackets
• For any syntax class X (over which x ranges) we define the syntax class Xseq (over which xseq ranges) as follows:

  

• Alternative phrases are listed in order of decreasing precedence.
• L and R indicate left and right association.
• The syntax of types binds more tightly than that of expressions.
• Each iterated construct (e.g. match) extends as far to the right as possible. Hence a case inside a case, fn, or fun may have to be enclosed in parentheses.