examples/OCaml-Kaleidoscope/Chapter3/ast.ml

   1 (*===----------------------------------------------------------------------===
   2  * Abstract Syntax Tree (aka Parse Tree)
   3  *===----------------------------------------------------------------------===*)
   4
   5 (* expr - Base type for all expression nodes. *)
   6 type expr =
   7   (* variant for numeric literals like "1.0". *)
   8   | Number of float
   9
  10   (* variant for referencing a variable, like "a". *)
  11   | Variable of string
  12
  13   (* variant for a binary operator. *)
  14   | Binary of char * expr * expr
  15
  16   (* variant for function calls. *)
  17   | Call of string * expr array
  18
  19 (* proto - This type represents the "prototype" for a function, which captures
  20  * its name, and its argument names (thus implicitly the number of arguments the
  21  * function takes). *)
  22 type proto = Prototype of string * string array
  23
  24 (* func - This type represents a function definition itself. *)
  25 type func = Function of proto * expr