wcc+ww: //ww:module-reset boundary directive; package-less files keep module "" (#16 PREP-main)

Driver twins emit the line-comment directive only before package-less
files (peekpackage==nil); both lexers tokenize it (TK_MODRESET, appended
=87 so existing token values hold) and both parsers reset curmod — a
package-less file's decls get module "" instead of inheriting the last
bundled package (the sticky-curmod leak, task #11). Withdrawn
alternative: injecting 'package main' flips non-entry symbols
bare->main-prefixed (FFI-visible, broke 764). Codegen-neutral by proof:
bare symbols preserved, both stages emit byte-identical asm for a
directive-bearing combined. Transitional until strict-package rejects
package-less files outright. Includes 737 bad-deep pin for the
PREP-peek >2048 edge + 904/toktest rows for the new token.

lib/ww/lex/lex.ww

@@ -56,6 +56,9 @@ type lex = struct {
 	line:   i32,
 	col:    i32,
 	errs:   i32,
+	// a `//ww:module-reset` directive was seen in the last skipped run;
+	// lexnext emits TK_MODRESET before the next real token (#16 opt-B).
+	modreset: i32,
 };
 
 export fn lexinit(l: *lex, file: str, src: *u8, len: u64) void = {
@@ -66,6 +69,7 @@ export fn lexinit(l: *lex, file: str, src: *u8, len: u64) void = {
 	l.line = 1;
 	l.col = 1;
 	l.errs = 0;
+	l.modreset = 0;
 };
 
 // srcb — byte at offset; helper that lifts the cast out of indexing.
@@ -127,6 +131,26 @@ fn skipws(l: *lex) bool = {
 			let c2: i32 = lpeek(l, 1u64);
 			if (c2 == '/') {
 				lget(l); lget(l);	// consume '//'
+				// #16 opt-B: recognize the driver's curmod-reset
+				// boundary directive `//ww:module-reset` (whole
+				// line) and flag it; lexnext emits TK_MODRESET.
+				// The body is then skipped like any comment.
+				// Mirrors cstage lex.c skipws. Compare via lpeek
+				// (no consume) so the skip loop below is unchanged.
+				let dir: str = "ww:module-reset";
+				let di: i32 = 0;
+				let matched: bool = true;
+				for (di < dir.len) {
+					if (lpeek(l, di: u64) != dir[di]: i32) {
+						matched = false; break;
+					};
+					di += 1;
+				};
+				if (matched) {
+					let nx: i32 = lpeek(l, dir.len: u64);
+					if (nx == '\n') { l.modreset = 1; }
+					else { if (nx < 0) { l.modreset = 1; }; };
+				};
 				for (true) {
 					let cx: i32 = lpeek(l, 0u64);
 					if (cx < 0) { return false; };
@@ -629,12 +653,19 @@ export fn lexnext(l: *lex, out: *tok) void = {
 	out.text = empty;
 	out.tsuffix = empty;
 
-	if (!skipws(l)) {
-		let p: pos; curpos(l, &p);
-		emitsimple(&p, tkind.TK_EOF, out);
+	let more: bool = skipws(l);
+	let start: pos; curpos(l, &start);
+	// A `//ww:module-reset` seen in the skipped run surfaces as its own
+	// token before the next real one (#16 opt-B boundary reset).
+	if (l.modreset != 0) {
+		l.modreset = 0;
+		emitsimple(&start, tkind.TK_MODRESET, out);
+		return;
+	};
+	if (!more) {
+		emitsimple(&start, tkind.TK_EOF, out);
 		return;
 	};
-	let start: pos; curpos(l, &start);
 	let c: i32 = lpeek(l, 0u64);
 
 	if (c >= 0) {

lib/ww/lex/tok.ww

@@ -118,7 +118,10 @@ type tkind = enum i32 {
 	TK_YIELD  = 84,
 	TK_ENUM   = 85,
 	TK_MODULE = 86,	// `module foo;` — directory-as-module decl
-	TK_LAST   = 87,
+	TK_MODRESET = 87,	// `//ww:module-reset` driver bundle boundary:
+				// reset curmod to "" before a package-less file
+				// (#16 option-B; cstage TK_MODRESET twin)
+	TK_LAST   = 88,
 };
 
 // ---- Pos / Tok --------------------------------------------------------
@@ -240,6 +243,7 @@ export fn tokname(k: tkind) str = {
 	case tkind.TK_UNDER:    return "_";
 	case tkind.TK_ENUM:     return "enum";
 	case tkind.TK_MODULE:   return "package";
+	case tkind.TK_MODRESET: return "//ww:module-reset";
 
 	case tkind.TK_LPAREN:   return "(";
 	case tkind.TK_RPAREN:   return ")";

lib/ww/lex/toktest.ww

@@ -128,11 +128,12 @@ fn checkname(k: tkind, want: str) void = {
 	signalled = 185; checkname(tkind.TK_ARROW, "->");
 	signalled = 186; checkname(tkind.TK_FATARROW, "=>");
 
-	signalled = 187; checkname(tkind.TK_LAST, "<last>");
+	signalled = 187; checkname(tkind.TK_MODRESET, "//ww:module-reset");
+	signalled = 188; checkname(tkind.TK_LAST, "<last>");
 
 	// Unknown kind → the post-switch fallback. TK_LAST is the highest
-	// named value (87); 88 is out of band, exercising the "<?>" tail.
-	signalled = 188; checkname(88: tkind, "<?>");
+	// named value (88); 89 is out of band, exercising the "<?>" tail.
+	signalled = 189; checkname(89: tkind, "<?>");
 };
 
 fn checkkw(s: str, want: tkind) void = {

lib/ww/parse/parse.ww

@@ -411,6 +411,22 @@ export fn parsefile(p: *parser) *node = {
 			p.curmod = name;
 			continue;
 		};
+		// `//ww:module-reset` — bundle boundary before a package-less
+		// file. Reset curmod to "" so the file's decls (and its own
+		// `import os;`) are attributed to the primary module, not the
+		// preceding bundled package. Codegen-neutral: "" curmod keeps
+		// bare symbols. (#16 option-B; closes task #11.)
+		// Driver-emitted ONLY before package-less files; a hand-placed
+		// directive after a mid-file `package` would strip subsequent
+		// decls to bare — that usage is deliberate-only.
+		if (p.curkind == tkind.TK_MODRESET) {
+			advance(p);
+			let empty: str;
+			empty.ptr = nil;
+			empty.len = 0;
+			p.curmod = empty;
+			continue;
+		};
 		let attrs = parseattrs(p);
 		let exported: i32 = 0;
 		if (p.curkind == tkind.TK_EXPORT) { exported = 1; advance(p); };