Bugfixeses: Consistent escaping in various literals. Double

backslash codes for single backslash. Output clause can be empty.

* parser.l (char_esc): Backslash handled.
Use internal_error rather than abort.
(REGCHAR, LITCHAR): Backslash added to lexical syntax.

* parser.y (output_clause): Allow empty output clause.

2 files changed, 12 insertions, 6 deletions

diff --git a/parser.l b/parser.l
index 437d504c..0fd39c5b 100644
--- a/parser.l
+++ b/parser.l
@@ -34,12 +34,14 @@
 #include <errno.h>
 #include <dirent.h>
 #include <wchar.h>
+#include <setjmp.h>
 #include "config.h"
 #include "lib.h"
 #include "y.tab.h"
 #include "gc.h"
 #include "stream.h"
 #include "utf8.h"
+#include "unwind.h"
 #include "parser.h"
 
 #define YY_INPUT(buf, result, max_size)           \
@@ -145,9 +147,11 @@ static wchar_t char_esc(int letter)
   case '"': return L'"';
   case '\'': return L'\'';
   case '`': return L'`';
+  case '/': return L'/';
+  case '\\': return L'\\';
   }
 
-  abort();
+  internal_error("unhandled escape character");
 }
 
 static wchar_t num_esc(char *num)
@@ -425,10 +429,10 @@ UONLY   {U2}{U}|{U3}{U}{U}|{U4}{U}{U}{U}
                 }
 
 
-<REGEX>[\\][abtnvfre]   {
-                          yylval.chr = char_esc(yytext[1]);
-                          return REGCHAR;
-                        }
+<REGEX>[\\][abtnvfre\\]         {
+                                  yylval.chr = char_esc(yytext[1]);
+                                  return REGCHAR;
+                                }
 
 <REGEX>[\\](x{HEX}+|{OCT}+)     {
                                   yylval.chr = num_esc(yytext + 1);
@@ -516,7 +520,7 @@ UONLY   {U2}{U}|{U3}{U}{U}|{U4}{U}{U}{U}
                   return yytext[0];
                 }
 
-<STRLIT,CHRLIT,QSILIT>[\\][abtnvfre"`'] {
+<STRLIT,CHRLIT,QSILIT>[\\][abtnvfre"`'\\] {
                                           yylval.chr = char_esc(yytext[1]);
                                           return LITCHAR;
                                         }
diff --git a/parser.y b/parser.y
index e6e66d1d..2ad2d53f 100644
--- a/parser.y
+++ b/parser.y
@@ -271,6 +271,8 @@ output_clause : OUTPUT ')' o_elems '\n'
                 END newl        { $$ = nil;
                                   yyerror("obsolete output syntax: trailing material"); }
               | OUTPUT ')' newl
+                END newl        { $$ = list(output_s, nao); }
+              | OUTPUT ')' newl
                 out_clauses
                 END newl        { $$ = list(output_s, $4, nao); }
               | OUTPUT exprs ')' newl