Celestin Apprentice 4/Apprentice-Release4.iso/Source Code/C/Applications/SML⁄NJ 93+/Documentation/examples/spread/parse.sig

Text File | 1995-12-30 | 294 b | 15 lines | [TEXT/R*ch]

signature PARSE =
sig
    structure F : FORMULA
    val parse : string -> F.formula
end

(* Grammar (in order of precedence):

    exp ->  NUM  |  ( exp )  |  [ exp , exp ]
    exp ->  exp * exp  |   exp / exp
    exp ->  exp + exp  |  exp - exp
    exp ->  "if" exp "then" exp "else" exp
*)