lib: drop non-Hare extras (ascii.digitval, bytes.copy, fmt.errpos)

ascii.digitval/isidstart/isidpart are lexer-private, not Hare-stdlib.
Moved into lib/ww/lex/lex.ww as fn (renamed digitval to hexval since
its sole job is the \\xHH escape decoder).

bytes.copy and fmt.errpos have no Hare counterpart and no external
callers; gone.

selfhost/cmd/w6c/main.combined.ww

@@ -1000,33 +1000,6 @@ export fn isxdigit(c: rune) bool = {
 	return false;
 };
 
-// digitval — value of `c` as a hex/decimal digit. void variant means
-// `c` isn't a hex digit. Useful when scanning numeric literals.
-export fn digitval(c: rune) (i32 | void) = {
-	if (isdigit(c)) { return (c - 48): i32; };
-	if (c >= 65) {
-		if (c <= 70) { return ((c - 65) + 10): i32; };
-	};
-	if (c >= 97) {
-		if (c <= 102) { return ((c - 97) + 10): i32; };
-	};
-	return;
-};
-
-// isidstart / isidpart — identifier classes used by the lexer.
-// Alpha or '_' starts; alnum or '_' continues.
-export fn isidstart(c: rune) bool = {
-	if (isalpha(c)) { return true; };
-	if (c == 95) { return true; };	// '_'
-	return false;
-};
-
-export fn isidpart(c: rune) bool = {
-	if (isalnum(c)) { return true; };
-	if (c == 95) { return true; };
-	return false;
-};
-
 // tolower / toupper — fold ASCII case. Non-letters pass through.
 export fn tolower(c: rune) rune = {
 	if (isupper(c)) { return c + 32; };
@@ -1057,6 +1030,34 @@ use ascii;
 use mem;
 use tok;
 
+// isidstart / isidpart — identifier classification. Lexer-local
+// because the "alpha or '_' / alnum or '_'" set isn't part of Hare's
+// ascii::; ascii::isalpha + the '_' check live here instead.
+fn isidstart(c: rune) bool = {
+	if (ascii.isalpha(c)) { return true; };
+	if (c == 95) { return true; };	// '_'
+	return false;
+};
+
+fn isidpart(c: rune) bool = {
+	if (ascii.isalnum(c)) { return true; };
+	if (c == 95) { return true; };
+	return false;
+};
+
+// hexval — value of `c` as a hex digit (0..15) or void if not a hex
+// digit. Used by string-literal `\xHH` escapes.
+fn hexval(c: rune) (i32 | void) = {
+	if (ascii.isdigit(c)) { return (c - 48): i32; };
+	if (c >= 65) {
+		if (c <= 70) { return ((c - 65) + 10): i32; };	// 'A'..'F'
+	};
+	if (c >= 97) {
+		if (c <= 102) { return ((c - 97) + 10): i32; };	// 'a'..'f'
+	};
+	return;
+};
+
 type lex = struct {
 	file:   str,
 	src:    *u8,	// raw bytes; not necessarily NUL-terminated
@@ -1286,8 +1287,8 @@ fn escape(l: *lex, out: *i32) bool = {
 		// keeps the explicit "return false on impossible-void" path
 		// for symmetry with the other lexer error sites. Use `!`
 		// once we have a panic-with-position helper.
-		let h: i32 = ascii.digitval(hi: rune)!;
-		let lv: i32 = ascii.digitval(lo: rune)!;
+		let h: i32 = hexval(hi: rune)!;
+		let lv: i32 = hexval(lo: rune)!;
 		*out = (h << 4) | lv;
 		return true;
 	};
@@ -1530,12 +1531,12 @@ fn lexnum(l: *lex, start: *pos, out: *tok) void = {
 
 	let pc: i32 = lpeek(l, 0u64);
 	if (pc >= 0) {
-		if (ascii.isidstart(pc: rune)) {
+		if (isidstart(pc: rune)) {
 			let sb: u64 = l.lpos;
 			for (true) {
 				let cc: i32 = lpeek(l, 0u64);
 				if (cc < 0) { break; };
-				if (!ascii.isidpart(cc: rune)) { break; };
+				if (!isidpart(cc: rune)) { break; };
 				lget(l);
 			};
 			let sl: u64 = l.lpos - sb;
@@ -1579,7 +1580,7 @@ fn lexident(l: *lex, start: *pos, out: *tok) void = {
 	for (true) {
 		let c: i32 = lpeek(l, 0u64);
 		if (c < 0) { break; };
-		if (!ascii.isidpart(c: rune)) { break; };
+		if (!isidpart(c: rune)) { break; };
 		lget(l);
 	};
 	let n: u64 = l.lpos - begin;
@@ -1728,7 +1729,7 @@ export fn lexnext(l: *lex, out: *tok) void = {
 	let c: i32 = lpeek(l, 0u64);
 
 	if (c >= 0) {
-		if (ascii.isidstart(c: rune)) { lexident(l, &start, out); return; };
+		if (isidstart(c: rune)) { lexident(l, &start, out); return; };
 		if (ascii.isdigit(c: rune))   { lexnum(l, &start, out); return; };
 	};
 

selfhost/cmd/wwdump/main.combined.ww

@@ -1000,33 +1000,6 @@ export fn isxdigit(c: rune) bool = {
 	return false;
 };
 
-// digitval — value of `c` as a hex/decimal digit. void variant means
-// `c` isn't a hex digit. Useful when scanning numeric literals.
-export fn digitval(c: rune) (i32 | void) = {
-	if (isdigit(c)) { return (c - 48): i32; };
-	if (c >= 65) {
-		if (c <= 70) { return ((c - 65) + 10): i32; };
-	};
-	if (c >= 97) {
-		if (c <= 102) { return ((c - 97) + 10): i32; };
-	};
-	return;
-};
-
-// isidstart / isidpart — identifier classes used by the lexer.
-// Alpha or '_' starts; alnum or '_' continues.
-export fn isidstart(c: rune) bool = {
-	if (isalpha(c)) { return true; };
-	if (c == 95) { return true; };	// '_'
-	return false;
-};
-
-export fn isidpart(c: rune) bool = {
-	if (isalnum(c)) { return true; };
-	if (c == 95) { return true; };
-	return false;
-};
-
 // tolower / toupper — fold ASCII case. Non-letters pass through.
 export fn tolower(c: rune) rune = {
 	if (isupper(c)) { return c + 32; };
@@ -1057,6 +1030,34 @@ use ascii;
 use mem;
 use tok;
 
+// isidstart / isidpart — identifier classification. Lexer-local
+// because the "alpha or '_' / alnum or '_'" set isn't part of Hare's
+// ascii::; ascii::isalpha + the '_' check live here instead.
+fn isidstart(c: rune) bool = {
+	if (ascii.isalpha(c)) { return true; };
+	if (c == 95) { return true; };	// '_'
+	return false;
+};
+
+fn isidpart(c: rune) bool = {
+	if (ascii.isalnum(c)) { return true; };
+	if (c == 95) { return true; };
+	return false;
+};
+
+// hexval — value of `c` as a hex digit (0..15) or void if not a hex
+// digit. Used by string-literal `\xHH` escapes.
+fn hexval(c: rune) (i32 | void) = {
+	if (ascii.isdigit(c)) { return (c - 48): i32; };
+	if (c >= 65) {
+		if (c <= 70) { return ((c - 65) + 10): i32; };	// 'A'..'F'
+	};
+	if (c >= 97) {
+		if (c <= 102) { return ((c - 97) + 10): i32; };	// 'a'..'f'
+	};
+	return;
+};
+
 type lex = struct {
 	file:   str,
 	src:    *u8,	// raw bytes; not necessarily NUL-terminated
@@ -1286,8 +1287,8 @@ fn escape(l: *lex, out: *i32) bool = {
 		// keeps the explicit "return false on impossible-void" path
 		// for symmetry with the other lexer error sites. Use `!`
 		// once we have a panic-with-position helper.
-		let h: i32 = ascii.digitval(hi: rune)!;
-		let lv: i32 = ascii.digitval(lo: rune)!;
+		let h: i32 = hexval(hi: rune)!;
+		let lv: i32 = hexval(lo: rune)!;
 		*out = (h << 4) | lv;
 		return true;
 	};
@@ -1530,12 +1531,12 @@ fn lexnum(l: *lex, start: *pos, out: *tok) void = {
 
 	let pc: i32 = lpeek(l, 0u64);
 	if (pc >= 0) {
-		if (ascii.isidstart(pc: rune)) {
+		if (isidstart(pc: rune)) {
 			let sb: u64 = l.lpos;
 			for (true) {
 				let cc: i32 = lpeek(l, 0u64);
 				if (cc < 0) { break; };
-				if (!ascii.isidpart(cc: rune)) { break; };
+				if (!isidpart(cc: rune)) { break; };
 				lget(l);
 			};
 			let sl: u64 = l.lpos - sb;
@@ -1579,7 +1580,7 @@ fn lexident(l: *lex, start: *pos, out: *tok) void = {
 	for (true) {
 		let c: i32 = lpeek(l, 0u64);
 		if (c < 0) { break; };
-		if (!ascii.isidpart(c: rune)) { break; };
+		if (!isidpart(c: rune)) { break; };
 		lget(l);
 	};
 	let n: u64 = l.lpos - begin;
@@ -1728,7 +1729,7 @@ export fn lexnext(l: *lex, out: *tok) void = {
 	let c: i32 = lpeek(l, 0u64);
 
 	if (c >= 0) {
-		if (ascii.isidstart(c: rune)) { lexident(l, &start, out); return; };
+		if (isidstart(c: rune)) { lexident(l, &start, out); return; };
 		if (ascii.isdigit(c: rune))   { lexnum(l, &start, out); return; };
 	};