From 35a28a58b38fb90cbe7c9596d60af2b3c1bd52a3 Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Thu, 1 Aug 2019 14:11:33 -0300
Subject: [PATCH] Details

- removed rule about RCS from makefile
- comments and nitpicking in 'llex.c'
---
 llex.c   | 20 +++++++++++++-------
 makefile |  1 -
 2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/llex.c b/llex.c
index d99d9015..f88057fe 100644
--- a/llex.c
+++ b/llex.c
@@ -211,8 +211,16 @@ static int check_next2 (LexState *ls, const char *set) {
 
 /* LUA_NUMBER */
 /*
-** this function is quite liberal in what it accepts, as 'luaO_str2num'
-** will reject ill-formed numerals.
+** This function is quite liberal in what it accepts, as 'luaO_str2num'
+** will reject ill-formed numerals. Roughly, it accepts the following
+** pattern:
+**
+**   %d(%x|%.|([Ee][+-]?))* | 0[Xx](%x|%.|([Pp][+-]?))*
+**
+** The only tricky part is to accept [+-] only after a valid exponent
+** mark, to avoid reading '3-4' or '0xe+1' as a single number.
+**
+** The caller might have already read an initial dot.
 */
 static int read_numeral (LexState *ls, SemInfo *seminfo) {
   TValue obj;
@@ -223,15 +231,13 @@ static int read_numeral (LexState *ls, SemInfo *seminfo) {
   if (first == '0' && check_next2(ls, "xX"))  /* hexadecimal? */
     expo = "Pp";
   for (;;) {
-    if (check_next2(ls, expo))  /* exponent part? */
+    if (check_next2(ls, expo))  /* exponent mark? */
       check_next2(ls, "-+");  /* optional exponent sign */
-    if (lisxdigit(ls->current))
-      save_and_next(ls);
-    else if (ls->current == '.')
+    else if (lisxdigit(ls->current) || ls->current == '.')  /* '%x|%.' */
       save_and_next(ls);
     else break;
   }
-  if (lislalnum(ls->current))  /* is numeral touching an alpha num? */
+  if (lislalpha(ls->current))  /* is numeral touching a letter? */
     save_and_next(ls);  /* force an error */
   save(ls, '\0');
   if (luaO_str2num(luaZ_buffer(ls->buff), &obj) == 0)  /* format error? */
diff --git a/makefile b/makefile
index cb6cece8..cf238aeb 100644
--- a/makefile
+++ b/makefile
@@ -107,7 +107,6 @@ $(LUAC_T): $(LUAC_O) $(CORE_T)
 	$(CC) -o $@ $(MYLDFLAGS) $(LUAC_O) $(CORE_T) $(LIBS) $(MYLIBS)
 
 clean:
-	rcsclean -u
 	$(RM) $(ALL_T) $(ALL_O)
 
 depend: