Implement guards, and start work on ↑ and ↓

1 files changed, 44 insertions, 30 deletions

diff --git a/eval.c b/eval.c
index 3958a98..7d9afbe 100644
--- a/eval.c
+++ b/eval.c
@@ -21,38 +21,34 @@ Datum monadop(Datum, Datum);
 Datum dyadop(Datum, Datum);
 Datum *lookup(Datum);
 
-int bindingstrengths[13][13] = {
-/*	A  F  H  MO DO AF (  )  [  ]  ←  IS N */
-	6, 3, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* A */
-	2, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* F */
-	0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* H */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* MO */
-	5, 5, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* DO */
-	2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* AF */
-	0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, /* ( */
-	7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, /* ) */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* [ */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* ] */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* ← */
-	1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* IS */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 0, 0, /* N */
+int bindingstrengths[11][11] = {
+/*	A  F  H  MO DO AF (  )  ←  IS N */
+	6, 3, 0, 4, 0, 0, 0, 0, 0, 0, 0, /* A */
+	2, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, /* F */
+	0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, /* H */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* MO */
+	5, 5, 5, 0, 0, 0, 0, 0, 0, 0, 0, /* DO */
+	2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* AF */
+	0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, /* ( */
+	7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, /* ) */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* ← */
+	1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* IS */
+	0, 0, 0, 0, 0, 0, 0, 0, 8, 0, 0, /* N */
 };
 
-evalfn evalfns[13][13] = {
-/*	A  F  H  MO DO AF (  )  [  ] ← IS N */
-	strand, dyadfun, 0, monadop, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* A */
-	monadfun, 0, 0, monadop, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* F */
-	0, 0, 0, monadop, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* H */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* MO */
-	dyadop, dyadop, dyadop, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* DO */
-	monadfun, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* AF */
-	0, 0, 0, 0, 0, 0, 0, parens, 0, 0, 0, 0, 0, /* ( */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* ) */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* [ */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* ] */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* ← */
-	assign, assign, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* IS */
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, nameis, 0, 0, /* N */	
+evalfn evalfns[11][11] = {
+/*	A  F  H  MO DO AF (  )  ←  IS N */
+	strand, dyadfun, 0, monadop, 0, 0, 0, 0, 0, 0, 0, /* A */
+	monadfun, 0, 0, monadop, 0, 0, 0, 0, 0, 0, 0, /* F */
+	0, 0, 0, monadop, 0, 0, 0, 0, 0, 0, 0, /* H */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* MO */
+	dyadop, dyadop, dyadop, 0, 0, 0, 0, 0, 0, 0, 0, /* DO */
+	monadfun, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* AF */
+	0, 0, 0, 0, 0, 0, 0, parens, 0, 0, 0, /* ( */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* ) */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* ← */
+	assign, assign, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* IS */
+	0, 0, 0, 0, 0, 0, 0, 0, nameis, 0, 0, /* N */	
 };
 
 Datum *
@@ -107,6 +103,7 @@ retry:
 			return nil;
 		}else{
 			Datum new = fn(stmt->toks[offset],stmt->toks[offset+1]);
+			traceprint("handler fn done\n");
 			if(stmt->toks[offset].tag == ArrayTag)
 				freearray(stmt->toks[offset].array);
 			if(stmt->toks[offset+1].tag == ArrayTag)
@@ -125,6 +122,23 @@ retry:
 		}
 	}
 	if(stmt->ntoks == 1){
+		if(stmt->guard){
+			int guardOK = 1;
+			if(stmt->toks[0].tag != ArrayTag)
+				guardOK = 0;
+			else if(stmt->toks[0].array->size != 1)
+				guardOK = 0;
+			else if(stmt->toks[0].array->type != AtypeInt)
+				guardOK = 0;
+			else if(stmt->toks[0].array->intdata[0] != 0 && stmt->toks[0].array->intdata[0] != 1)
+				guardOK = 0;
+			if(!guardOK){
+				print("Guard expected single valued boolean\n");
+				exits(nil);
+			}
+			if(stmt->toks[0].array->intdata[0] == 1)
+				return eval(stmt->guard);
+		}
 		if(stmt->next)
 			return eval(stmt->next);
 		else