Implement better dnfs semantics

6 files changed, 22 insertions, 19 deletions

diff --git a/apl9.h b/apl9.h
index d86d659..acbfcbb 100644
--- a/apl9.h
+++ b/apl9.h
@@ -143,7 +143,7 @@ struct QuadnameDef
 
 /* Function prototypes for the different source files */
 /* main.c */
-Datum *evalline(Rune *);
+Datum *evalline(Rune *, int);
 Rune *prompt(Rune *);
 
 /* print.c */
@@ -153,7 +153,7 @@ Rune *pparray(Array *);
 Rune *ppoperator(Operator);
 
 /* lexer.c */
-Statement *lexline(Rune *);
+Statement *lexline(Rune *, int);
 
 /* array.c */
 Array *mkscalarint(vlong);
@@ -172,7 +172,7 @@ int comparearray(Array *, Array *, int);
 Array *fillelement(Array *);
 
 /* eval.c */
-Datum *eval(Statement *);
+Datum *eval(Statement *, int);
 
 /* symbol.c */
 Symbol *getsym(Symtab *, Rune *);
diff --git a/eval.c b/eval.c
index 7d9afbe..e794a38 100644
--- a/eval.c
+++ b/eval.c
@@ -52,7 +52,7 @@ evalfn evalfns[11][11] = {
 };
 
 Datum *
-eval(Statement *stmt)
+eval(Statement *stmt, int toplevel)
 {
 	errormsg = nil;
 
@@ -122,6 +122,9 @@ retry:
 		}
 	}
 	if(stmt->ntoks == 1){
+		int stop = 0;
+		if(toplevel == 0 && !stmt->toks[0].shy)
+			stop = 1;
 		if(stmt->guard){
 			int guardOK = 1;
 			if(stmt->toks[0].tag != ArrayTag)
@@ -137,10 +140,10 @@ retry:
 				exits(nil);
 			}
 			if(stmt->toks[0].array->intdata[0] == 1)
-				return eval(stmt->guard);
+				return eval(stmt->guard, toplevel);
 		}
-		if(stmt->next)
-			return eval(stmt->next);
+		if(stmt->next && !stop)
+			return eval(stmt->next, toplevel);
 		else
 			return stmt->toks;
 	}else
@@ -215,7 +218,7 @@ parens(Datum left, Datum right)
 	/* evaluate a parenthesis expression and return the result */
 	USED(right);
 	traceprint("PARENS: %S\n", ppdatums(left.stmt.toks, left.stmt.ntoks));
-	Datum *result = eval(&left.stmt);
+	Datum *result = eval(&left.stmt, 1);
 	if(result[0].tag == ArrayTag)
 		result[0].array->stranded = 0;
 	result[0].shy = 0;
diff --git a/functions.c b/functions.c
index c82a9cb..7266f28 100644
--- a/functions.c
+++ b/functions.c
@@ -138,7 +138,7 @@ runfunc(Function f, Array *left, Array *right)
 		omega->undefined = 0;
 		incref(right);
 
-		Datum *dfnres = evalline(f.dfn);
+		Datum *dfnres = evalline(f.dfn, 0);
 		freesymtab(currentsymtab);
 		currentsymtab = tmpsymtab;
 		return (*dfnres).array; /* TODO what if the evaluation failed */
diff --git a/lexer.c b/lexer.c
index b2990c8..f734912 100644
--- a/lexer.c
+++ b/lexer.c
@@ -7,7 +7,7 @@
 Rune primhybridnames[] = L"/\⌿⍀";
 
 Statement *
-lexline(Rune *line)
+lexline(Rune *line, int toplevel)
 {
 	int offset = 0;
 	int len = runestrlen(line);
@@ -25,7 +25,7 @@ lexline(Rune *line)
 		}else if(runestrchr(L"←⋄⍝⍬", line[offset])){
 			switch(line[offset]){
 			case L'←': stmt->toks[stmt->ntoks].tag = ArrowTag; break;
-			case L'⋄': stmt->next = lexline(&line[offset+1]); goto end;
+			case L'⋄': stmt->next = lexline(&line[offset+1], toplevel); goto end;
 			case L'⍝': goto end;
 			case L'⍬':
 				stmt->toks[stmt->ntoks].tag = ArrayTag;
@@ -34,7 +34,7 @@ lexline(Rune *line)
 				break;
 			}
 			offset++;
-		}else if(line[offset] == ':'){
+		}else if(!toplevel && line[offset] == ':'){
 			Rune buf[MAX_LINE_LENGTH];
 			Rune *p = buf;
 			offset++;
@@ -44,7 +44,7 @@ lexline(Rune *line)
 				offset++;
 			}
 			*p = 0;
-			stmt->guard = lexline(buf);
+			stmt->guard = lexline(buf, toplevel);
 			stmt->ntoks--;
 		}else if(line[offset] == '{'){
 			Rune buf[MAX_LINE_LENGTH];
@@ -81,7 +81,7 @@ lexline(Rune *line)
 			*p = 0;
 			offset++;
 			stmt->toks[stmt->ntoks].tag = LParTag;
-			stmt->toks[stmt->ntoks].stmt = *lexline(buf);
+			stmt->toks[stmt->ntoks].stmt = *lexline(buf, toplevel);
 			stmt->ntoks++;
 			stmt->toks[stmt->ntoks].tag = RParTag;
 		}else if(p = runestrchr(primfuncnames, line[offset])){
diff --git a/main.c b/main.c
index ef6e948..96a6d07 100644
--- a/main.c
+++ b/main.c
@@ -30,7 +30,7 @@ main(int argc, char *argv[])
 	while(!off){
 		checkmem("main loop");
 		Rune *input = prompt(L"\t");
-		Datum *result = evalline(input);
+		Datum *result = evalline(input, 1);
 		if(result == nil){
 			if(errormsg == nil)
 				off = 1;
@@ -64,10 +64,10 @@ prompt(Rune *pr)
 }
 
 Datum *
-evalline(Rune *line)
+evalline(Rune *line, int toplevel)
 {
-	Statement *stmts = lexline(line);
-	Datum *result = eval(stmts);
+	Statement *stmts = lexline(line, toplevel);
+	Datum *result = eval(stmts, toplevel);
 	if(result)
 		return result;
 	else{
diff --git a/quadnames.c b/quadnames.c
index 14c431e..bb191c5 100644
--- a/quadnames.c
+++ b/quadnames.c
@@ -45,7 +45,7 @@ Datum *
 getquad(void)
 {
 	Rune *input = prompt(L"⎕:\n\t");
-	Datum *result = evalline(input);
+	Datum *result = evalline(input, 1);
 	/* TODO check that the expression doesn't fail */
 	return result;
 }