refactor: add IGRAPH_I_STRINGIFY

Author: szhorvat

include/igraph_decls.h

@@ -40,6 +40,10 @@
 #  define IGRAPH_ASSUME(expr) /* empty */
 #endif
 
+/* IGRAPH_I_STRINGIFY(X) evaluates X and converts the result to a string. */
+#define IGRAPH_I_STRINGIFY_I(X) #X
+#define IGRAPH_I_STRINGIFY(X) IGRAPH_I_STRINGIFY_I(X)
+
 /* Include the definition of macros controlling symbol visibility */
 #include "igraph_export.h"
 

src/core/printing.c

@@ -52,9 +52,7 @@
  */
 #ifdef DBL_DIG
     /* Use DBL_DIG to determine the maximum precision used for %g */
-    #define STRINGIFY_HELPER(x) #x
-    #define STRINGIFY(x) STRINGIFY_HELPER(x)
-    #define IGRAPH_REAL_PRINTF_PRECISE_FORMAT "%." STRINGIFY(DBL_DIG) "g"
+    #define IGRAPH_REAL_PRINTF_PRECISE_FORMAT "%." IGRAPH_I_STRINGIFY(DBL_DIG) "g"
 #else
     /* Assume a precision of 15 digits for %g, which is what IEEE-754 doubles require. */
     #define IGRAPH_REAL_PRINTF_PRECISE_FORMAT "%.15g"

tests/benchmarks/igraph_qsort.c

@@ -4,9 +4,6 @@
 
 /* This program benchmarks igraph_qsort() indirectly through vector_sort() */
 
-#define STRINGIFY(x) #x
-#define TOSTRING(x) STRINGIFY(x)
-
 int main(void) {
     igraph_vector_int_t vec;
 
@@ -24,7 +21,7 @@ int main(void) {
     for (igraph_integer_t i=0; i < N; i++) {
         VECTOR(vec)[i] = RNG_INTEGER(0, N-1);
     }
-    BENCH("Sort vector of length " TOSTRING(N), igraph_vector_int_sort(&vec));
+    BENCH("Sort vector of length " IGRAPH_I_STRINGIFY(N), igraph_vector_int_sort(&vec));
 
 #undef N
 #define N 1000000
@@ -33,7 +30,7 @@ int main(void) {
     for (igraph_integer_t i=0; i < N; i++) {
         VECTOR(vec)[i] = RNG_INTEGER(0, N-1);
     }
-    BENCH("Sort vector of length " TOSTRING(N), igraph_vector_int_sort(&vec));
+    BENCH("Sort vector of length " IGRAPH_I_STRINGIFY(N), igraph_vector_int_sort(&vec));
 
 #undef N
 #define N 100000
@@ -42,7 +39,7 @@ int main(void) {
     for (igraph_integer_t i=0; i < N; i++) {
         VECTOR(vec)[i] = RNG_INTEGER(0, N-1);
     }
-    BENCH("Sort vector of length " TOSTRING(N), igraph_vector_int_sort(&vec));
+    BENCH("Sort vector of length " IGRAPH_I_STRINGIFY(N), igraph_vector_int_sort(&vec));
 
     RNG_END();