X-Git-Url: https://code.consxy.com/gitweb/gitweb.cgi?p=clnl;a=blobdiff_plain;f=src%2Fmain%2Fparse.lisp;h=4f331ca5016a8dca661423994a30d6c8e91cfb57;hp=6197d30191752aed9451c5e90d681e3722b7bc0d;hb=89cb3482de1fefc2d8e5f67e1e04a0790e8cd243;hpb=b25736698f7f7f9670f8e2408055556c4dd99ef0

diff --git a/src/main/parse.lisp b/src/main/parse.lisp
index 6197d30..4f331ca 100644
--- a/src/main/parse.lisp
+++ b/src/main/parse.lisp
@@ -68,7 +68,8 @@ DESCRIPTION:
   lowest precedence, and all reporters should have 10 as the precedence.
 
   The possible values for ARG are :agentset, :boolean, :number, :command-block,
-  or t for wildcard.
+  :string, or t for wildcard.  For optional arguments, ARG can be a list of the form
+  (ARG :optional) where ARG is one of the aforementioned values.
 
   The need for a parser between the lexer and the transpiler is because NetLogo
   needs two passes to turn into something that can be used.  This is the only entry
@@ -192,21 +193,33 @@ DESCRIPTION:
   (error "Can't have a prim that wants a token and has a precedence of less than 20: ~A" prim))
  (let*
   ((args (if (prim-is-infix prim) (cdr (prim-args prim)) (prim-args prim)))
-   (half-parsed-remainder (parse-internal (cdr lexed-ast) :remaining-args (append args (list :done-with-args))))
+   (half-parsed-remainder
+    (parse-internal (cdr lexed-ast) :remaining-args (append args (list :done-with-args))))
    (breakpoint (or
                 (position-if (lambda (form) (or (not (listp form)) (not (eql :arg (car form))))) half-parsed-remainder)
                 (length half-parsed-remainder)))
    (already-parsed-limbo-forms
     (subseq half-parsed-remainder breakpoint (min (length args) (length half-parsed-remainder))))
+   (num-optional-forms (- (length args) breakpoint))
    (middle-forms
     (cons
      (if
       (prim-is-infix prim)
-      (reconfigure-due-to-precedence prev-item prim (mapcar #'cadr (subseq half-parsed-remainder 0 breakpoint)))
+      ; There's a potential bug here about infix operators with optional forms, where the first item is optional
+      ; I don't consider that super likely though...
+      (append
+       (reconfigure-due-to-precedence prev-item prim (mapcar #'cadr (subseq half-parsed-remainder 0 breakpoint)))
+       (loop :repeat num-optional-forms :collect :optional))
       (cons
        (prim-name prim)
-       (mapcar #'cadr (subseq half-parsed-remainder 0 breakpoint))))
-     already-parsed-limbo-forms)))
+       (append
+        (mapcar #'cadr (subseq half-parsed-remainder 0 breakpoint))
+        (loop :repeat num-optional-forms :collect :optional)))) ; we save the place for optionals for the transpiler
+     already-parsed-limbo-forms)));)
+  (let
+   ((arg-at-bp (nth breakpoint args)))
+   (when (and arg-at-bp (or (not (listp arg-at-bp)) (not (find :optional arg-at-bp))))
+    (error "Stopped collecting arguments, but non optional arguments remain")))
   (append
    (butlast middle-forms)
    (parse-internal
@@ -366,6 +379,10 @@ DESCRIPTION:
 (defprim :green () 10)
 (defprim :white () 10)
 
+; booleans
+(defprim :true () 10)
+(defprim :false () 10)
+
 (defstructureprim :globals)
 (defstructureprim :breed)
 (defstructureprim :turtles-own)