X-Git-Url: https://ocean-lang.org/code/?a=blobdiff_plain;f=csrc%2Foceani.mdc;h=06f71be3268da0b30eb962be214eab1c4d23f558;hb=a571467ffc33a814c65f5a410a4f70509787b9aa;hp=86b3e3cb844ddd5fde3ffe8c9243bb21e962a735;hpb=4bee4f99bc7a0ab4dcd635766acdd15e96f29f5f;p=ocean

diff --git a/csrc/oceani.mdc b/csrc/oceani.mdc
index 86b3e3c..06f71be 100644
--- a/csrc/oceani.mdc
+++ b/csrc/oceani.mdc
@@ -123,6 +123,9 @@ structures can be used.
 	#define config2context(_conf) container_of(_conf, struct parse_context, \
 		config)
 
+###### Parser: reduce
+	struct parse_context *c = config2context(config);
+
 ###### Parser: code
 
 	#include <unistd.h>
@@ -1002,7 +1005,7 @@ like "if" and the code following it.
 ###### Grammar
 
 	$void
-	OpenScope -> ${ scope_push(config2context(config)); }$
+	OpenScope -> ${ scope_push(c); }$
 
 Each variable records a scope depth and is in one of four states:
 
@@ -1093,7 +1096,7 @@ list of in_scope names.
 
 			v = t->previous;
 			free_value(t->val);
-			if (t->min_depth == 0)
+			if (t->depth == 0)
 				// This is a global constant
 				free_exec(t->where_decl);
 			free(t);
@@ -1455,7 +1458,9 @@ propagation is needed.
 ###### core functions
 
 	static struct type *propagate_types(struct exec *prog, struct parse_context *c, int *ok,
-	                                    struct type *type, int rules)
+	                                    struct type *type, int rules);
+	static struct type *__propagate_types(struct exec *prog, struct parse_context *c, int *ok,
+	                                      struct type *type, int rules)
 	{
 		struct type *t;
 
@@ -1476,6 +1481,16 @@ propagation is needed.
 		return Tnone;
 	}
 
+	static struct type *propagate_types(struct exec *prog, struct parse_context *c, int *ok,
+	                                    struct type *type, int rules)
+	{
+		struct type *ret = __propagate_types(prog, c, ok, type, rules);
+
+		if (c->parse_error)
+			*ok = 0;
+		return ret;
+	}
+
 #### Interpreting
 
 Interpreting an `exec` doesn't require anything but the `exec`.  State
@@ -1663,7 +1678,6 @@ make a copy of an array with controllable depth.
 		$0->array.member = $<4;
 		$0->array.vsize = NULL;
 		{
-		struct parse_context *c = config2context(config);
 		char tail[3];
 		mpq_t num;
 		if (number_parse(num, tail, $2.txt) == 0)
@@ -1686,13 +1700,12 @@ make a copy of an array with controllable depth.
 	}$
 
 	| [ IDENTIFIER ] Type ${ {
-		struct parse_context *c = config2context(config);
 		struct variable *v = var_ref(c, $2.txt);
 
 		if (!v)
-			tok_err(config2context(config), "error: name undeclared", &$2);
+			tok_err(c, "error: name undeclared", &$2);
 		else if (!v->constant)
-			tok_err(config2context(config), "error: array size must be a constant", &$2);
+			tok_err(c, "error: array size must be a constant", &$2);
 
 		$0 = calloc(1, sizeof(struct type));
 		*($0) = array_prototype;
@@ -1731,9 +1744,9 @@ make a copy of an array with controllable depth.
 
 ###### print binode cases
 	case Index:
-		print_exec(b->left, -1, 0);
+		print_exec(b->left, -1, bracket);
 		printf("[");
-		print_exec(b->right, -1, 0);
+		print_exec(b->right, -1, bracket);
 		printf("]");
 		break;
 
@@ -1746,13 +1759,11 @@ make a copy of an array with controllable depth.
 		t = propagate_types(b->left, c, ok, NULL, rules & Rnoconstant);
 		if (!t || t->compat != array_compat) {
 			type_err(c, "error: %1 cannot be indexed", prog, t, 0, NULL);
-			*ok = 0;
 			return NULL;
 		} else {
 			if (!type_compat(type, t->array.member, rules)) {
 				type_err(c, "error: have %1 but need %2", prog,
 				         t->array.member, rules, type);
-				*ok = 0;
 			}
 			return t->array.member;
 		}
@@ -1919,7 +1930,7 @@ function will be needed.
 	case Xfieldref:
 	{
 		struct fieldref *f = cast(fieldref, e);
-		print_exec(f->left, -1, 0);
+		print_exec(f->left, -1, bracket);
 		printf(".%.*s", f->name.len, f->name.txt);
 		break;
 	}
@@ -1949,19 +1960,15 @@ function will be needed.
 			         f->left, st, 0, NULL);
 		else if (f->index == -2) {
 			f->index = find_struct_index(st, f->name);
-			if (f->index < 0) {
+			if (f->index < 0)
 				type_err(c, "error: cannot find requested field in %1",
 				         f->left, st, 0, NULL);
-				*ok = 0;
-			}
 		}
 		if (f->index >= 0) {
 			struct type *ft = st->structure.fields[f->index].type;
-			if (!type_compat(type, ft, rules)) {
+			if (!type_compat(type, ft, rules))
 				type_err(c, "error: have %1 but need %2", prog,
 				         ft, rules, type);
-				*ok = 0;
-			}
 			return ft;
 		}
 		break;
@@ -1994,41 +2001,57 @@ function will be needed.
 
 ###### top level grammar
 	DeclareStruct -> struct IDENTIFIER FieldBlock ${ {
-		struct type *t =
-			add_type(config2context(config), $2.txt, &structure_prototype);
-		int cnt = 0;
-		struct fieldlist *f;
-
-		for (f = $3; f; f=f->prev)
-			cnt += 1;
-
-		t->structure.nfields = cnt;
-		t->structure.fields = calloc(cnt, sizeof(struct field));
-		f = $3;
-		while (cnt > 0) {
-			cnt -= 1;
-			t->structure.fields[cnt] = f->f;
-			f->f.init = val_prepare(Tnone);
-			f = f->prev;
-		}
-	} }$
+			struct type *t =
+				add_type(c, $2.txt, &structure_prototype);
+			int cnt = 0;
+			struct fieldlist *f;
+
+			for (f = $3; f; f=f->prev)
+				cnt += 1;
+
+			t->structure.nfields = cnt;
+			t->structure.fields = calloc(cnt, sizeof(struct field));
+			f = $3;
+			while (cnt > 0) {
+				cnt -= 1;
+				t->structure.fields[cnt] = f->f;
+				f->f.init = val_prepare(Tnone);
+				f = f->prev;
+			}
+		} }$
+		| DeclareStruct NEWLINE
 
+	$void
+	Newlines -> NEWLINE
+		| Newlines NEWLINE
+	Open -> {
+		| Newlines {
+	Close -> }
+		| Newlines }
 	$*fieldlist
-	FieldBlock -> Open SimpleFieldList Close ${ $0 = $<2; }$
-		| Open Newlines SimpleFieldList Close ${ $0 = $<3; }$
-		| : FieldList  ${ $0 = $<2; }$
-
-	FieldList -> Field NEWLINE ${ $0 = $<1; }$
-		| FieldList NEWLINE ${ $0 = $<1; }$
-		| FieldList Field NEWLINE ${
+	FieldBlock -> Open FieldList } ${ $0 = $<2; }$
+		| Open SimpleFieldList } ${ $0 = $<2; }$
+		| : FieldList $$NEWLINE ${ $0 = $<2; }$
+
+	FieldList -> FieldLines ${ $0 = $<1; }$
+		| Newlines FieldLines ${ $0 = $<2; }$
+	FieldLines -> SimpleFieldListLine ${ $0 = $<1; }$
+		| FieldLines SimpleFieldListLine ${
 			$2->prev = $<1;
 			$0 = $<2;
 		}$
 
-	SimpleFieldList -> Field ; ${ $0 = $<1; }$
-		| SimpleFieldList Field ; ${
-			$2->prev = $<1;
-			$0 = $<2;
+	SimpleFieldListLine -> SimpleFieldList NEWLINE ${ $0 = $<1; }$
+		| SimpleFieldListLine NEWLINE ${ $0 = $<1; }$
+		| ERROR NEWLINE ${ tok_err(c, "Syntax error in struct field", &$1); }$
+
+	SimpleFieldList -> Field ${ $0 = $<1; }$
+		| SimpleFieldList ; Field ${
+			$3->prev = $<1;
+			$0 = $<3;
+		}$
+		| SimpleFieldList ; ${
+			$0 = $<1;
 		}$
 
 	Field -> IDENTIFIER : Type = Expression ${ {
@@ -2040,10 +2063,10 @@ function will be needed.
 			$0->f.init = val_prepare($0->f.type);
 			do {
 				ok = 1;
-				propagate_types($<5, config2context(config), &ok, $3, 0);
+				propagate_types($<5, c, &ok, $3, 0);
 			} while (ok == 2);
 			if (!ok)
-				config2context(config)->parse_error = 1;
+				c->parse_error = 1;
 			else
 				$0->f.init = interp_exec($5);
 		} }$
@@ -2146,7 +2169,7 @@ an executable.
 			if (number_parse($0->val.num, tail, $1.txt) == 0)
 				mpq_init($0->val.num);
 				if (tail[0])
-					tok_err(config2context(config), "error: unsupported number suffix",
+					tok_err(c, "error: unsupported number suffix",
 					        &$1);
 			}
 			}$
@@ -2157,7 +2180,7 @@ an executable.
 			char tail[3];
 			string_parse(&$1, '\\', &$0->val.str, tail);
 			if (tail[0])
-				tok_err(config2context(config), "error: unsupported string suffix",
+				tok_err(c, "error: unsupported string suffix",
 				        &$1);
 			}
 			}$
@@ -2168,7 +2191,7 @@ an executable.
 			char tail[3];
 			string_parse(&$1, '\\', &$0->val.str, tail);
 			if (tail[0])
-				tok_err(config2context(config), "error: unsupported string suffix",
+				tok_err(c, "error: unsupported string suffix",
 				        &$1);
 			}
 			}$
@@ -2189,11 +2212,9 @@ an executable.
 	case Xval:
 	{
 		struct val *val = cast(val, prog);
-		if (!type_compat(type, val->val.type, rules)) {
+		if (!type_compat(type, val->val.type, rules))
 			type_err(c, "error: expected %1%r found %2",
 			           prog, type, rules, val->val.type);
-			*ok = 0;
-		}
 		return val->val.type;
 	}
 
@@ -2257,38 +2278,38 @@ link to find the primary instance.
 
 	$*var
 	VariableDecl -> IDENTIFIER : ${ {
-		struct variable *v = var_decl(config2context(config), $1.txt);
+		struct variable *v = var_decl(c, $1.txt);
 		$0 = new_pos(var, $1);
 		$0->var = v;
 		if (v)
 			v->where_decl = $0;
 		else {
-			v = var_ref(config2context(config), $1.txt);
+			v = var_ref(c, $1.txt);
 			$0->var = v;
-			type_err(config2context(config), "error: variable '%v' redeclared",
+			type_err(c, "error: variable '%v' redeclared",
 			         $0, NULL, 0, NULL);
-			type_err(config2context(config), "info: this is where '%v' was first declared",
+			type_err(c, "info: this is where '%v' was first declared",
 			         v->where_decl, NULL, 0, NULL);
 		}
 	} }$
 	    | IDENTIFIER :: ${ {
-		struct variable *v = var_decl(config2context(config), $1.txt);
+		struct variable *v = var_decl(c, $1.txt);
 		$0 = new_pos(var, $1);
 		$0->var = v;
 		if (v) {
 			v->where_decl = $0;
 			v->constant = 1;
 		} else {
-			v = var_ref(config2context(config), $1.txt);
+			v = var_ref(c, $1.txt);
 			$0->var = v;
-			type_err(config2context(config), "error: variable '%v' redeclared",
+			type_err(c, "error: variable '%v' redeclared",
 			         $0, NULL, 0, NULL);
-			type_err(config2context(config), "info: this is where '%v' was first declared",
+			type_err(c, "info: this is where '%v' was first declared",
 			         v->where_decl, NULL, 0, NULL);
 		}
 	} }$
 	    | IDENTIFIER : Type ${ {
-		struct variable *v = var_decl(config2context(config), $1.txt);
+		struct variable *v = var_decl(c, $1.txt);
 		$0 = new_pos(var, $1);
 		$0->var = v;
 		if (v) {
@@ -2296,16 +2317,16 @@ link to find the primary instance.
 			v->where_set = $0;
 			v->val = val_prepare($<3);
 		} else {
-			v = var_ref(config2context(config), $1.txt);
+			v = var_ref(c, $1.txt);
 			$0->var = v;
-			type_err(config2context(config), "error: variable '%v' redeclared",
+			type_err(c, "error: variable '%v' redeclared",
 			         $0, NULL, 0, NULL);
-			type_err(config2context(config), "info: this is where '%v' was first declared",
+			type_err(c, "info: this is where '%v' was first declared",
 			         v->where_decl, NULL, 0, NULL);
 		}
 	} }$
 	    | IDENTIFIER :: Type ${ {
-		struct variable *v = var_decl(config2context(config), $1.txt);
+		struct variable *v = var_decl(c, $1.txt);
 		$0 = new_pos(var, $1);
 		$0->var = v;
 		if (v) {
@@ -2314,25 +2335,25 @@ link to find the primary instance.
 			v->val = val_prepare($<3);
 			v->constant = 1;
 		} else {
-			v = var_ref(config2context(config), $1.txt);
+			v = var_ref(c, $1.txt);
 			$0->var = v;
-			type_err(config2context(config), "error: variable '%v' redeclared",
+			type_err(c, "error: variable '%v' redeclared",
 			         $0, NULL, 0, NULL);
-			type_err(config2context(config), "info: this is where '%v' was first declared",
+			type_err(c, "info: this is where '%v' was first declared",
 			         v->where_decl, NULL, 0, NULL);
 		}
 	} }$
 
 	$*exec
 	Variable -> IDENTIFIER ${ {
-		struct variable *v = var_ref(config2context(config), $1.txt);
+		struct variable *v = var_ref(c, $1.txt);
 		$0 = new_pos(var, $1);
 		if (v == NULL) {
 			/* This might be a label - allocate a var just in case */
-			v = var_decl(config2context(config), $1.txt);
+			v = var_decl(c, $1.txt);
 			if (v) {
-				v->val = val_prepare(Tlabel);
-				v->val.label = &v->val;
+				v->val = val_prepare(Tnone);
+				v->where_decl = $0;
 				v->where_set = $0;
 			}
 		}
@@ -2342,9 +2363,9 @@ link to find the primary instance.
 
 	$*type
 	Type -> IDENTIFIER ${
-		$0 = find_type(config2context(config), $1.txt);
+		$0 = find_type(c, $1.txt);
 		if (!$0) {
-			tok_err(config2context(config),
+			tok_err(c,
 				"error: undefined type", &$1);
 
 			$0 = Tnone;
@@ -2384,7 +2405,6 @@ link to find the primary instance.
 		struct variable *v = var->var;
 		if (!v) {
 			type_err(c, "%d:BUG: no variable!!", prog, NULL, 0, NULL); // NOTEST
-			*ok = 0;					// NOTEST
 			return Tnone;					// NOTEST
 		}
 		if (v->merged)
@@ -2394,9 +2414,11 @@ link to find the primary instance.
 			         prog, NULL, 0, NULL);
 			type_err(c, "info: name was defined as a constant here",
 			         v->where_decl, NULL, 0, NULL);
-			*ok = 0;
 			return v->val.type;
 		}
+		if (v->val.type == Tnone && v->where_decl == prog)
+			type_err(c, "error: variable used but not declared: %v",
+			         prog, NULL, 0, NULL);
 		if (v->val.type == NULL) {
 			if (type && *ok != 0) {
 				v->val = val_prepare(type);
@@ -2410,7 +2432,6 @@ link to find the primary instance.
 			         type, rules, v->val.type);
 			type_err(c, "info: this is where '%v' was set to %1", v->where_set,
 			         v->val.type, rules, NULL);
-			*ok = 0;
 		}
 		if (!type)
 			return v->val.type;
@@ -2459,8 +2480,11 @@ room for ambiguity, so a full conditional expression is allowed in there.
 
 ###### Grammar
 
+	$LEFT if $$ifelse
+	## expr precedence
+
 	$*exec
-	Expression -> BoolExpr if Expression else Expression ${ {
+	Expression -> Expression if Expression else Expression $$ifelse ${ {
 			struct binode *b1 = new(binode);
 			struct binode *b2 = new(binode);
 			b1->op = CondExpr;
@@ -2471,17 +2495,19 @@ room for ambiguity, so a full conditional expression is allowed in there.
 			b2->right = $<5;
 			$0 = b1;
 		} }$
-		| BoolExpr ${ $0 = $<1; }$
+		## expression grammar
 
 ###### print binode cases
 
 	case CondExpr:
 		b2 = cast(binode, b->right);
-		print_exec(b2->left, -1, 0);
+		if (bracket) printf("(");
+		print_exec(b2->left, -1, bracket);
 		printf(" if ");
-		print_exec(b->left, -1, 0);
+		print_exec(b->left, -1, bracket);
 		printf(" else ");
-		print_exec(b2->right, -1, 0);
+		print_exec(b2->right, -1, bracket);
+		if (bracket) printf(")");
 		break;
 
 ###### propagate binode cases
@@ -2527,73 +2553,83 @@ if the result would make a difference.
 	OrElse,
 	Not,
 
-###### Grammar
+###### expr precedence
+	$LEFT or
+	$LEFT and
+	$LEFT not
 
-	$*exec
-	BoolExpr -> BoolExpr or BTerm ${ {
+###### expression grammar
+		| Expression or Expression ${ {
 			struct binode *b = new(binode);
 			b->op = Or;
 			b->left = $<1;
 			b->right = $<3;
 			$0 = b;
 		} }$
-		| BoolExpr or else BTerm ${ {
+		| Expression or else Expression ${ {
 			struct binode *b = new(binode);
 			b->op = OrElse;
 			b->left = $<1;
 			b->right = $<4;
 			$0 = b;
 		} }$
-		| BTerm ${ $0 = $<1; }$
 
-	BTerm -> BTerm and BFact ${ {
+		| Expression and Expression ${ {
 			struct binode *b = new(binode);
 			b->op = And;
 			b->left = $<1;
 			b->right = $<3;
 			$0 = b;
 		} }$
-		| BTerm and then BFact ${ {
+		| Expression and then Expression ${ {
 			struct binode *b = new(binode);
 			b->op = AndThen;
 			b->left = $<1;
 			b->right = $<4;
 			$0 = b;
 		} }$
-		| BFact ${ $0 = $<1; }$
 
-	BFact -> not BFact ${ {
+		| not Expression ${ {
 			struct binode *b = new(binode);
 			b->op = Not;
 			b->right = $<2;
 			$0 = b;
 		} }$
-		## other BFact
 
 ###### print binode cases
 	case And:
-		print_exec(b->left, -1, 0);
+		if (bracket) printf("(");
+		print_exec(b->left, -1, bracket);
 		printf(" and ");
-		print_exec(b->right, -1, 0);
+		print_exec(b->right, -1, bracket);
+		if (bracket) printf(")");
 		break;
 	case AndThen:
-		print_exec(b->left, -1, 0);
+		if (bracket) printf("(");
+		print_exec(b->left, -1, bracket);
 		printf(" and then ");
-		print_exec(b->right, -1, 0);
+		print_exec(b->right, -1, bracket);
+		if (bracket) printf(")");
 		break;
 	case Or:
-		print_exec(b->left, -1, 0);
+		if (bracket) printf("(");
+		print_exec(b->left, -1, bracket);
 		printf(" or ");
-		print_exec(b->right, -1, 0);
+		print_exec(b->right, -1, bracket);
+		if (bracket) printf(")");
 		break;
 	case OrElse:
-		print_exec(b->left, -1, 0);
+		if (bracket) printf("(");
+		print_exec(b->left, -1, bracket);
 		printf(" or else ");
-		print_exec(b->right, -1, 0);
+		print_exec(b->right, -1, bracket);
+		if (bracket) printf(")");
 		break;
 	case Not:
+		if (bracket) printf("(");
 		printf("not ");
-		print_exec(b->right, -1, 0);
+		print_exec(b->right, -1, bracket);
+		if (bracket) printf(")");
 		break;
 
 ###### propagate binode cases
@@ -2605,11 +2641,9 @@ if the result would make a difference.
 		/* both must be Tbool, result is Tbool */
 		propagate_types(b->left, c, ok, Tbool, 0);
 		propagate_types(b->right, c, ok, Tbool, 0);
-		if (type && type != Tbool) {
+		if (type && type != Tbool)
 			type_err(c, "error: %1 operation found where %2 expected", prog,
 				   Tbool, 0, type);
-			*ok = 0;
-		}
 		return Tbool;
 
 ###### interp binode cases
@@ -2668,15 +2702,17 @@ expression operator.
 	Eql,
 	NEql,
 
-###### other BFact
-	| Expr CMPop Expr ${ {
+###### expr precedence
+	$LEFT < > <= >= == != CMPop
+
+###### expression grammar
+	| Expression CMPop Expression ${ {
 		struct binode *b = new(binode);
 		b->op = $2.op;
 		b->left = $<1;
 		b->right = $<3;
 		$0 = b;
 	} }$
-	| Expr ${ $0 = $<1; }$
 
 ###### Grammar
 
@@ -2696,7 +2732,8 @@ expression operator.
 	case GtrEq:
 	case Eql:
 	case NEql:
-		print_exec(b->left, -1, 0);
+		if (bracket) printf("(");
+		print_exec(b->left, -1, bracket);
 		switch(b->op) {
 		case Less:   printf(" < "); break;
 		case LessEq: printf(" <= "); break;
@@ -2706,7 +2743,8 @@ expression operator.
 		case NEql:   printf(" != "); break;
 		default: abort();		// NOTEST
 		}
-		print_exec(b->right, -1, 0);
+		print_exec(b->right, -1, bracket);
+		if (bracket) printf(")");
 		break;
 
 ###### propagate binode cases
@@ -2725,11 +2763,9 @@ expression operator.
 			if (t)
 				t = propagate_types(b->left, c, ok, t, 0);
 		}
-		if (!type_compat(type, Tbool, 0)) {
+		if (!type_compat(type, Tbool, 0))
 			type_err(c, "error: Comparison returns %1 but %2 expected", prog,
 			            Tbool, rules, type);
-			*ok = 0;
-		}
 		return Tbool;
 
 ###### interp binode cases
@@ -2778,34 +2814,35 @@ precedence is handled better I might be able to discard this.
 	Absolute, Negate,
 	Bracket,
 
-###### Grammar
+###### expr precedence
+	$LEFT + - Eop
+	$LEFT * / % ++ Top
+	$LEFT Uop
 
-	$*exec
-	Expr -> Expr Eop Term ${ {
+###### expression grammar
+		| Expression Eop Expression ${ {
 			struct binode *b = new(binode);
 			b->op = $2.op;
 			b->left = $<1;
 			b->right = $<3;
 			$0 = b;
 		} }$
-		| Term ${ $0 = $<1; }$
 
-	Term -> Term Top Factor ${ {
+		| Expression Top Expression ${ {
 			struct binode *b = new(binode);
 			b->op = $2.op;
 			b->left = $<1;
 			b->right = $<3;
 			$0 = b;
 		} }$
-		| Factor ${ $0 = $<1; }$
 
-	Factor -> ( Expression ) ${ {
+		| ( Expression ) ${ {
 			struct binode *b = new_pos(binode, $1);
 			b->op = Bracket;
 			b->right = $<2;
 			$0 = b;
 		} }$
-		| Uop Factor ${ {
+		| Uop Expression ${ {
 			struct binode *b = new(binode);
 			b->op = $1.op;
 			b->right = $<2;
@@ -2833,7 +2870,8 @@ precedence is handled better I might be able to discard this.
 	case Divide:
 	case Concat:
 	case Rem:
-		print_exec(b->left, indent, 0);
+		if (bracket) printf("(");
+		print_exec(b->left, indent, bracket);
 		switch(b->op) {
 		case Plus:   fputs(" + ", stdout); break;
 		case Minus:  fputs(" - ", stdout); break;
@@ -2843,19 +2881,24 @@ precedence is handled better I might be able to discard this.
 		case Concat: fputs(" ++ ", stdout); break;
 		default: abort();	// NOTEST
 		}			// NOTEST
-		print_exec(b->right, indent, 0);
+		print_exec(b->right, indent, bracket);
+		if (bracket) printf(")");
 		break;
 	case Absolute:
+		if (bracket) printf("(");
 		printf("+");
-		print_exec(b->right, indent, 0);
+		print_exec(b->right, indent, bracket);
+		if (bracket) printf(")");
 		break;
 	case Negate:
+		if (bracket) printf("(");
 		printf("-");
-		print_exec(b->right, indent, 0);
+		print_exec(b->right, indent, bracket);
+		if (bracket) printf(")");
 		break;
 	case Bracket:
 		printf("(");
-		print_exec(b->right, indent, 0);
+		print_exec(b->right, indent, bracket);
 		printf(")");
 		break;
 
@@ -2872,22 +2915,18 @@ precedence is handled better I might be able to discard this.
 		 * unary ops fit here too */
 		propagate_types(b->left, c, ok, Tnum, 0);
 		propagate_types(b->right, c, ok, Tnum, 0);
-		if (!type_compat(type, Tnum, 0)) {
+		if (!type_compat(type, Tnum, 0))
 			type_err(c, "error: Arithmetic returns %1 but %2 expected", prog,
 			           Tnum, rules, type);
-			*ok = 0;
-		}
 		return Tnum;
 
 	case Concat:
 		/* both must be Tstr, result is Tstr */
 		propagate_types(b->left, c, ok, Tstr, 0);
 		propagate_types(b->right, c, ok, Tstr, 0);
-		if (!type_compat(type, Tstr, 0)) {
+		if (!type_compat(type, Tstr, 0))
 			type_err(c, "error: Concat returns %1 but %2 expected", prog,
 			           Tstr, rules, type);
-			*ok = 0;
-		}
 		return Tstr;
 
 	case Bracket:
@@ -3017,45 +3056,41 @@ is in-place.
 
 ###### Grammar
 
-	$void
-	OptNL -> Newlines
-		|
-
-	Newlines -> NEWLINE
-		| Newlines NEWLINE
-
 	$*binode
-	Open -> {
-		| NEWLINE {
-	Close -> }
-		| NEWLINE }
 	Block -> Open Statementlist Close ${ $0 = $<2; }$
-		| Open Newlines Statementlist Close ${ $0 = $<3; }$
 		| Open SimpleStatements } ${ $0 = reorder_bilist($<2); }$
-		| Open Newlines SimpleStatements } ${ $0 = reorder_bilist($<3); }$
-		| : Statementlist ${ $0 = $<2; }$
-		| : SimpleStatements ${ $0 = reorder_bilist($<2); }$
+		| : SimpleStatements $$NEWLINE ${ $0 = reorder_bilist($<2); }$
+		| : Statementlist $$NEWLINE ${ $0 = $<2; }$
 
 	Statementlist -> ComplexStatements ${ $0 = reorder_bilist($<1); }$
+		| Newlines ComplexStatements ${ $0 = reorder_bilist($<2); }$
 
 	ComplexStatements -> ComplexStatements ComplexStatement ${
-		$0 = new(binode);
-		$0->op = Block;
-		$0->left = $<1;
-		$0->right = $<2;
+			if ($2 == NULL) {
+				$0 = $<1;
+			} else {
+				$0 = new(binode);
+				$0->op = Block;
+				$0->left = $<1;
+				$0->right = $<2;
+			}
 		}$
-		| ComplexStatements NEWLINE ${ $0 = $<1; }$
 		| ComplexStatement ${
-		$0 = new(binode);
-		$0->op = Block;
-		$0->left = NULL;
-		$0->right = $<1;
+			if ($1 == NULL) {
+				$0 = NULL;
+			} else {
+				$0 = new(binode);
+				$0->op = Block;
+				$0->left = NULL;
+				$0->right = $<1;
+			}
 		}$
 
 	$*exec
-	ComplexStatement -> SimpleStatements NEWLINE ${
+	ComplexStatement -> SimpleStatementLine ${
 			$0 = reorder_bilist($<1);
 			}$
+		| ComplexStatement NEWLINE ${ $0 = $<1; }$
 		## ComplexStatement Grammar
 
 	$*binode
@@ -3073,7 +3108,11 @@ is in-place.
 			}$
 		| SimpleStatements ; ${ $0 = $<1; }$
 
+	SimpleStatementLine -> SimpleStatements NEWLINE ${ $0 = $<1; }$
+		| SimpleStatementLine NEWLINE ${ $0 = $<1; }$
+
 	SimpleStatement -> pass ${ $0 = NULL; }$
+		| ERROR ${ tok_err(c, "Syntax error in statement", &$1); }$
 		## SimpleStatement Grammar
 
 ###### print binode cases
@@ -3083,10 +3122,10 @@ is in-place.
 			if (b->left == NULL)
 				printf("pass");
 			else
-				print_exec(b->left, indent, 0);
+				print_exec(b->left, indent, bracket);
 			if (b->right) {
 				printf("; ");
-				print_exec(b->right, indent, 0);
+				print_exec(b->right, indent, bracket);
 			}
 		} else {
 			// block, one per line
@@ -3118,11 +3157,9 @@ is in-place.
 			if (t && t != Tnone && t != Tbool) {
 				if (!type)
 					type = t;
-				else if (t != type) {
+				else if (t != type)
 					type_err(c, "error: expected %1%r, found %2",
 					         e->left, type, rules, t);
-					*ok = 0;
-				}
 			}
 		}
 		return type;
@@ -3191,7 +3228,7 @@ same solution.
 		while (b) {
 			if (b->left) {
 				printf(" ");
-				print_exec(b->left, -1, 0);
+				print_exec(b->left, -1, bracket);
 				if (b->right)
 					printf(",");
 			}
@@ -3262,7 +3299,7 @@ it is declared, and error will be raised as the name is created as
 
 	| VariableDecl ${
 			if ($1->var->where_set == NULL) {
-				type_err(config2context(config),
+				type_err(c,
 				         "Variable declared with no type or value: %v",
 				         $1, NULL, 0, NULL);
 			} else {
@@ -3277,9 +3314,9 @@ it is declared, and error will be raised as the name is created as
 
 	case Assign:
 		do_indent(indent, "");
-		print_exec(b->left, indent, 0);
+		print_exec(b->left, indent, bracket);
 		printf(" = ");
-		print_exec(b->right, indent, 0);
+		print_exec(b->right, indent, bracket);
 		if (indent >= 0)
 			printf("\n");
 		break;
@@ -3288,7 +3325,7 @@ it is declared, and error will be raised as the name is created as
 		{
 		struct variable *v = cast(var, b->left)->var;
 		do_indent(indent, "");
-		print_exec(b->left, indent, 0);
+		print_exec(b->left, indent, bracket);
 		if (cast(var, b->left)->var->constant) {
 			if (v->where_decl == v->where_set) {
 				printf("::");
@@ -3306,7 +3343,7 @@ it is declared, and error will be raised as the name is created as
 		}
 		if (b->right) {
 			printf("= ");
-			print_exec(b->right, indent, 0);
+			print_exec(b->right, indent, bracket);
 		}
 		if (indent >= 0)
 			printf("\n");
@@ -3338,10 +3375,8 @@ it is declared, and error will be raised as the name is created as
 				propagate_types(b->left, c, ok, t,
 				                (b->op == Assign ? Rnoconstant : 0));
 		}
-		if (t && t->dup == NULL) {
+		if (t && t->dup == NULL)
 			type_err(c, "error: cannot assign value of type %1", b, t, 0, NULL);
-			*ok = 0;
-		}
 		return Tnone;
 
 		break;
@@ -3389,13 +3424,21 @@ function.
 		$0 = new_pos(binode, $1);
 		$0->op = Use;
 		$0->right = $<2;
+		if ($0->right->type == Xvar) {
+			struct var *v = cast(var, $0->right);
+			if (v->var->val.type == Tnone) {
+				/* Convert this to a label */
+				v->var->val = val_prepare(Tlabel);
+				v->var->val.label = &v->var->val;
+			}
+		}
 	}$
 
 ###### print binode cases
 
 	case Use:
 		do_indent(indent, "use ");
-		print_exec(b->right, -1, 0);
+		print_exec(b->right, -1, bracket);
 		if (indent >= 0)
 			printf("\n");
 		break;
@@ -3529,36 +3572,46 @@ defined.
 	$*cond_statement
 	// both ForThen and Whilepart open scopes, and CondSuffix only
 	// closes one - so in the first branch here we have another to close.
-	CondStatement -> ForThen WhilePart CondSuffix ${
+	CondStatement -> ForPart ThenPart WhilePart CondSuffix ${
+			$0 = $<4;
+			$0->forpart = $<1;
+			$0->thenpart = $<2;
+			$0->condpart = $3.condpart; $3.condpart = NULL;
+			$0->dopart = $3.dopart; $3.dopart = NULL;
+			var_block_close(c, CloseSequential);
+			}$
+		|  ForPart WhilePart CondSuffix ${
 			$0 = $<3;
-			$0->forpart = $1.forpart; $1.forpart = NULL;
-			$0->thenpart = $1.thenpart; $1.thenpart = NULL;
+			$0->forpart = $<1;
+			$0->thenpart = NULL;
 			$0->condpart = $2.condpart; $2.condpart = NULL;
 			$0->dopart = $2.dopart; $2.dopart = NULL;
-			var_block_close(config2context(config), CloseSequential);
+			var_block_close(c, CloseSequential);
 			}$
 		| WhilePart CondSuffix ${
 			$0 = $<2;
 			$0->condpart = $1.condpart; $1.condpart = NULL;
 			$0->dopart = $1.dopart; $1.dopart = NULL;
 			}$
-		| SwitchPart CondSuffix ${
-			$0 = $<2;
+		| SwitchPart CasePart CondSuffix ${
+			$0 = $<3;
 			$0->condpart = $<1;
+			$2->next = $0->casepart;
+			$0->casepart = $<2;
 			}$
 		| IfPart IfSuffix ${
 			$0 = $<2;
 			$0->condpart = $1.condpart; $1.condpart = NULL;
 			$0->thenpart = $1.thenpart; $1.thenpart = NULL;
 			// This is where we close an "if" statement
-			var_block_close(config2context(config), CloseSequential);
+			var_block_close(c, CloseSequential);
 			}$
 
 	CondSuffix -> IfSuffix ${
 			$0 = $<1;
 			// This is where we close scope of the whole
 			// "for" or "while" statement
-			var_block_close(config2context(config), CloseSequential);
+			var_block_close(c, CloseSequential);
 		}$
 		| CasePart CondSuffix ${
 			$0 = $<2;
@@ -3567,40 +3620,26 @@ defined.
 		}$
 
 	$*casepart
-	CasePart -> Newlines case Expression OpenScope Block ${
-			$0 = calloc(1,sizeof(struct casepart));
-			$0->value = $<3;
-			$0->action = $<5;
-			var_block_close(config2context(config), CloseParallel);
-		}$
-		| case Expression OpenScope Block ${
+	CasePart -> case Expression OpenScope Block ${
 			$0 = calloc(1,sizeof(struct casepart));
 			$0->value = $<2;
 			$0->action = $<4;
-			var_block_close(config2context(config), CloseParallel);
+			var_block_close(c, CloseParallel);
 		}$
+		| CasePart NEWLINE ${ $0 = $<1; }$
 
 	$*cond_statement
-	IfSuffix -> Newlines ${ $0 = new(cond_statement); }$
-		| Newlines else OpenScope Block ${
-			$0 = new(cond_statement);
-			$0->elsepart = $<4;
-			var_block_close(config2context(config), CloseElse);
-		}$
+	IfSuffix ->  ${ $0 = new(cond_statement); }$
+		| IfSuffix NEWLINE ${ $0 = $<1; }$
 		| else OpenScope Block ${
 			$0 = new(cond_statement);
 			$0->elsepart = $<3;
-			var_block_close(config2context(config), CloseElse);
-		}$
-		| Newlines else OpenScope CondStatement ${
-			$0 = new(cond_statement);
-			$0->elsepart = $<4;
-			var_block_close(config2context(config), CloseElse);
+			var_block_close(c, CloseElse);
 		}$
 		| else OpenScope CondStatement ${
 			$0 = new(cond_statement);
 			$0->elsepart = $<3;
-			var_block_close(config2context(config), CloseElse);
+			var_block_close(c, CloseElse);
 		}$
 
 	$*exec
@@ -3611,58 +3650,49 @@ defined.
 		|  for OpenScope Block ${
 			$0 = $<3;
 		}$
+		|  ForPart NEWLINE ${ $0 = $<1; }$
 
 	ThenPart -> then OpenScope SimpleStatements ${
 			$0 = reorder_bilist($<3);
-			var_block_close(config2context(config), CloseSequential);
+			var_block_close(c, CloseSequential);
 		}$
 		|  then OpenScope Block ${
 			$0 = $<3;
-			var_block_close(config2context(config), CloseSequential);
-		}$
-
-	ThenPartNL -> ThenPart OptNL ${
-			$0 = $<1;
+			var_block_close(c, CloseSequential);
 		}$
+		|  ThenPart NEWLINE ${ $0 = $<1; }$
 
 	// This scope is closed in CondSuffix
-	WhileHead -> while OpenScope Block ${
-		$0 = $<3;
-		}$
+	WhileHead -> while OpenScope Block ${ $0 = $<3;	}$
+		| WhileHead NEWLINE ${ $0 = $<1; }$
 
 	$cond_statement
-	ForThen -> ForPart OptNL ThenPartNL ${
-			$0.forpart = $<1;
-			$0.thenpart = $<3;
-		}$
-		| ForPart OptNL ${
-			$0.forpart = $<1;
-		}$
-
 	// This scope is closed in CondSuffix
 	WhilePart -> while OpenScope Expression Block ${
 			$0.type = Xcond_statement;
 			$0.condpart = $<3;
 			$0.dopart = $<4;
 		}$
-		| WhileHead OptNL do Block ${
+		| WhileHead do Block ${
 			$0.type = Xcond_statement;
 			$0.condpart = $<1;
-			$0.dopart = $<4;
+			$0.dopart = $<3;
 		}$
+		| WhilePart NEWLINE ${ $0 = $<1; }$
 
 	IfPart -> if OpenScope Expression OpenScope Block ${
 			$0.type = Xcond_statement;
 			$0.condpart = $<3;
 			$0.thenpart = $<5;
-			var_block_close(config2context(config), CloseParallel);
+			var_block_close(c, CloseParallel);
 		}$
-		| if OpenScope Block OptNL then OpenScope Block ${
+		| if OpenScope Block then OpenScope Block ${
 			$0.type = Xcond_statement;
 			$0.condpart = $<3;
-			$0.thenpart = $<7;
-			var_block_close(config2context(config), CloseParallel);
+			$0.thenpart = $<6;
+			var_block_close(c, CloseParallel);
 		}$
+		| IfPart NEWLINE ${ $0 = $<1; }$
 
 	$*exec
 	// This scope is closed in CondSuffix
@@ -3672,6 +3702,7 @@ defined.
 		| switch OpenScope Block ${
 			$0 = $<3;
 		}$
+		| SwitchPart NEWLINE ${ $0 = $<1; }$
 
 ###### print exec cases
 
@@ -3909,14 +3940,19 @@ various declarations in the parse context.
 
 	$void
 	Ocean -> DeclarationList
+		| Newlines DeclarationList
 
 	DeclarationList -> Declaration
 		| DeclarationList Declaration
 
-	Declaration -> DeclareConstant
+	Declaration -> Declaration NEWLINE
+		| DeclareConstant
 		| DeclareProgram
 		| DeclareStruct
-		| NEWLINE
+		| ERROR NEWLINE ${
+			tok_err(c,
+			        "error: unhandled parse error", &$1);
+		}$
 
 	## top level grammar
 
@@ -3946,19 +3982,20 @@ searching through for the Nth constant for decreasing N.
 ###### top level grammar
 
 	DeclareConstant -> const Open ConstList Close
-		| const Open Newlines ConstList Close
 		| const Open SimpleConstList }
-		| const Open Newlines SimpleConstList }
-		| const : ConstList
-		| const SimpleConstList
-
-	ConstList -> ComplexConsts
-	ComplexConsts -> ComplexConst ComplexConsts
-		| ComplexConst
-	ComplexConst -> SimpleConstList NEWLINE
-	SimpleConstList -> Const ; SimpleConstList
+		| const : ConstList $$NEWLINE
+		| const SimpleConstList NEWLINE
+
+	ConstList -> ConstLines
+		| Newlines ConstLines
+	ConstLines -> ConstLines SimpleConstLine
+		| SimpleConstLine
+	SimpleConstList -> SimpleConstList ; Const
 		| Const
-		| Const ; SimpleConstList ;
+		| SimpleConstList ;
+	SimpleConstLine -> SimpleConstList NEWLINE
+		| SimpleConstLine NEWLINE
+		| ERROR NEWLINE ${ tok_err(c, "Syntax error in constant", &$1); }$
 
 	$*type
 	CType -> Type	${ $0 = $<1; }$
@@ -3968,7 +4005,7 @@ searching through for the Nth constant for decreasing N.
 		int ok;
 		struct variable *v;
 
-		v = var_decl(config2context(config), $1.txt);
+		v = var_decl(c, $1.txt);
 		if (v) {
 			struct var *var = new_pos(var, $1);
 			v->where_decl = var;
@@ -3976,17 +4013,17 @@ searching through for the Nth constant for decreasing N.
 			var->var = v;
 			v->constant = 1;
 		} else {
-			v = var_ref(config2context(config), $1.txt);
-			tok_err(config2context(config), "error: name already declared", &$1);
-			type_err(config2context(config), "info: this is where '%v' was first declared",
+			v = var_ref(c, $1.txt);
+			tok_err(c, "error: name already declared", &$1);
+			type_err(c, "info: this is where '%v' was first declared",
 			         v->where_decl, NULL, 0, NULL);
 		}
 		do {
 			ok = 1;
-			propagate_types($5, config2context(config), &ok, $3, 0);
+			propagate_types($5, c, &ok, $3, 0);
 		} while (ok == 2);
 		if (!ok)
-			config2context(config)->parse_error = 1;
+			c->parse_error = 1;
 		else if (v) {
 			v->val = interp_exec($5);
 		}
@@ -4045,7 +4082,6 @@ analysis is a bit more interesting at this level.
 ###### top level grammar
 
 	DeclareProgram -> Program ${ {
-		struct parse_context *c = config2context(config);
 		if (c->prog)
 			type_err(c, "Program defined a second time",
 			         $1, NULL, 0, NULL);
@@ -4054,17 +4090,13 @@ analysis is a bit more interesting at this level.
 	} }$
 
 	$*binode
-	Program -> program OpenScope Varlist Block OptNL ${
+	Program -> program OpenScope Varlist Block ${
 		$0 = new(binode);
 		$0->op = Program;
 		$0->left = reorder_bilist($<3);
 		$0->right = $<4;
-		var_block_close(config2context(config), CloseSequential);
-		if (config2context(config)->scope_stack) abort();
-		}$
-		| ERROR ${
-			tok_err(config2context(config),
-			        "error: unhandled parse error", &$1);
+		var_block_close(c, CloseSequential);
+		if (c->scope_stack && !c->parse_error) abort();
 		}$
 
 	Varlist -> Varlist ArgDecl ${
@@ -4077,7 +4109,7 @@ analysis is a bit more interesting at this level.
 
 	$*var
 	ArgDecl -> IDENTIFIER ${ {
-		struct variable *v = var_decl(config2context(config), $1.txt);
+		struct variable *v = var_decl(c, $1.txt);
 		$0 = new(var);
 		$0->var = v;
 	} }$