enum: a member is defined as soon as it is declared, so later values can name it (appendix b.2.2)

1 files changed, 6 insertions, 2 deletions

diff --git a/src/compiler/builtins.zc b/src/compiler/builtins.zc
index 214d493..6dc586a 100644
--- a/src/compiler/builtins.zc
+++ b/src/compiler/builtins.zc
@@ -71,8 +71,10 @@ int ptagged(word t) {
 // enum name { A, B = 5 } is a plain enum: each member is a constant, plain (A)
 // and scoped (name.A). a member with a block of fields makes it a tagged enum
 // (see enum_tagged): enum name { circle { int r; }, dot }.
+// the first member of the enum being read, so a member's value can name the members before it; -1 outside
+int enum_open = 0 - 1;
 int kw_enum() {
-	char* n; char* en = 0; int first = npm, cnt = 0, tagged = 0, gi, nf, v = 0, et = 0, sk, ft; char* fname;
+	char* n; char* en = 0; int first = npm, cnt = 0, tagged = 0, gi, nf, v = 0, et = 0, sk, ft, rv = 0; char* fname;
 	stmtonly();
 	next();
 	if (tk == T_ID) { en = tv; next(); }
@@ -97,7 +99,9 @@ int kw_enum() {
 				expect(s_semi);
 			}
 			expect(s_rb);
-		} else if (accept(s_eq)) { pm_val[gi] = cexpr(); pm_exp[gi] = 1; }
+		} else { enum_open = first; if (accept(s_eq)) { pm_val[gi] = cexpr(); pm_exp[gi] = 1; } enum_open = 0 - 1; }
+		if (pm_exp[gi]) rv = pm_val[gi]; else if (!pm_nf[gi]) pm_val[gi] = rv;	// the running value, read by cprim
+		rv++;
 		cnt++;
 		if (!accept(s_comma)) break;
 		if (is_op(s_rb)) break;