Implement lexical scope instead of dynamic scope rules.

1 files changed, 4 insertions, 2 deletions

diff --git a/apl9.h b/apl9.h
index bbba10f..2cf0069 100644
--- a/apl9.h
+++ b/apl9.h
@@ -153,6 +153,7 @@ struct Function
 		QuadnameDef *quad;
 		FunctionTrain train;
 	};
+	DfnFrame *scope;
 	Array *left;
 };
 
@@ -219,7 +220,8 @@ struct DfnFrame
 	Array *right;
 	Datum *lefto;
 	Datum *righto;
-	DfnFrame *prev;
+	DfnFrame *prev; /* prev in the call stack */
+	DfnFrame *chain; /* prev in the lexical scope */
 };
 
 struct ThreadData
@@ -279,7 +281,7 @@ Datum *eval(Statement *, int);
 Symbol *getsym(Rune *, int);
 void initsymtab(void);
 DfnFrame *getcurrentdfn(void);
-DfnFrame *pushdfnframe(Rune *, Datum *, Datum *, Array *, Array *);
+DfnFrame *pushdfnframe(Rune *, DfnFrame *, Datum *, Datum *, Array *, Array *);
 void popdfnframe(void);
 vlong globalIO(void);
 void globalIOset(vlong);