muscle: factor the computation of variable names

[bison.git] / src / uniqstr.h

diff --git a/src/uniqstr.h b/src/uniqstr.h
index c986df07f23003d7a17ef71b0e90cc8db87536d8..143f7aae3ed725d79f43669cc0eb4f55a4e54146 100644 (file)
--- a/src/uniqstr.h
+++ b/src/uniqstr.h
@@ -1,6 +1,6 @@
 /* Keeping a unique copy of strings.
 
-   Copyright (C) 2002, 2003, 2008 Free Software Foundation, Inc.
+   Copyright (C) 2002-2003, 2008-2013 Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -29,23 +29,66 @@ typedef char const *uniqstr;
 /* Return the uniqstr for STR.  */
 uniqstr uniqstr_new (char const *str);
 
+/* Return a uniqstr built by vsprintf.  In order to simply concatenate
+   strings, use UNIQSTR_CONCAT, which is a convenient wrapper around
+   this function.  */
+uniqstr uniqstr_vsprintf (char const *format, ...)
+  __attribute__ ((__format__ (__printf__, 1, 2)));
+
 /* Two uniqstr values have the same value iff they are the same.  */
-#define UNIQSTR_EQ(USTR1, USTR2) ((USTR1) == (USTR2))
+# define UNIQSTR_EQ(Ustr1, Ustr2) (!!((Ustr1) == (Ustr2)))
+
+/* Compare two uniqstr a la strcmp: negative for <, nul for =, and
+   positive for >.  Undefined order, relies on addresses.  */
+int uniqstr_cmp(uniqstr u1, uniqstr u2);
 
-/* Compare two uniqstr a la strlen: negative for <, nul for =, and
-   positive for >.  */
-#define UNIQSTR_CMP(USTR1, USTR2) ((USTR1) - (USTR2))
+/* Die if STR is not a uniqstr.  */
+void uniqstr_assert (char const *str);
 
-/*--------------------------------------.
-| Initializing, destroying, debugging.  |
-`--------------------------------------*/
+/*----------------.
+| Concatenation.  |
+`----------------*/
+
+/* Concatenate at most 20 strings and return a uniqstr.  The goal of
+   this macro is to make the caller's code a little more succinct
+   without a trivial uniqstr_vsprintf format string to maintain
+   (for example, "%s%s%s") while still benefitting from gcc's type
+   checking.  Unfortunately, because of the missing format string in the
+   macro invocation, the argument number reported by gcc for a bad
+   argument type is 1 too large.  */
+# define UNIQSTR_CONCAT(...)                                            \
+  uniqstr_vsprintf (UNIQSTR_GEN_FORMAT (__VA_ARGS__,                    \
+                                        "%s", "%s", "%s", "%s", "%s",   \
+                                        "%s", "%s", "%s", "%s", "%s",   \
+                                        "%s", "%s", "%s", "%s", "%s",   \
+                                        "%s", "%s", "%s", "%s", "%s"),  \
+                    __VA_ARGS__)
+
+# define UNIQSTR_GEN_FORMAT(F1,  F2,  F3,  F4,  F5,     \
+                           F6,  F7,  F8,  F9,  F10,     \
+                           F11, F12, F13, F14, F15,     \
+                           F16, F17, F18, F19, F20,     \
+                           ...)                         \
+  UNIQSTR_GEN_FORMAT_ (__VA_ARGS__,                     \
+                       "", "", "", "", "",              \
+                       "", "", "", "", "",              \
+                       "", "", "", "", "",              \
+                       "", "", "", "", "")
+
+# define UNIQSTR_GEN_FORMAT_(F1,  F2,  F3,  F4,  F5,            \
+                            F6,  F7,  F8,  F9,  F10,            \
+                            F11, F12, F13, F14, F15,            \
+                            F16, F17, F18, F19, F20, ...)       \
+  F1  F2  F3  F4  F5  F6  F7  F8  F9  F10                       \
+  F11 F12 F13 F14 F15 F16 F17 F18 F19 F20
+
+/*--------------------.
+| Table of uniqstrs.  |
+`--------------------*/
 
 /* Create the string table.  */
 void uniqstrs_new (void);
 
-/* Die if STR is not a uniqstr.  */
-void uniqstr_assert (char const *str);
-
 /* Free all the memory allocated for symbols.  */
 void uniqstrs_free (void);