Added priv/linkage.h and renamed priv/template2.h => priv/template_undef.h.

Make all examples c++ compatible, except those using cspan.h
Removed: crange_obj()
Renamed: crange_make() => crange_init()
Renamed: cspan_make() => cspan_init()
Renamed: cstr_NULL => cstr_null
Renamed: csview_NULL => csview_null

21 files changed, 148 insertions, 85 deletions

diff --git a/include/stc/algo/coroutine.h b/include/stc/algo/coroutine.h
index 67ea5a40..5cd6d68f 100644
--- a/include/stc/algo/coroutine.h
+++ b/include/stc/algo/coroutine.h
@@ -56,7 +56,7 @@ int main(void) {
     return 0;
 }
 */
-#include <stc/ccommon.h>
+#include "../ccommon.h"
 
 enum {
     cco_state_final = -1,
diff --git a/include/stc/algo/crange.h b/include/stc/algo/crange.h
index 56c317da..34ed541b 100644
--- a/include/stc/algo/crange.h
+++ b/include/stc/algo/crange.h
@@ -27,14 +27,15 @@
 
 int main()
 {
-    crange r1 = crange_make(80, 90);
+    crange r1 = crange_init(80, 90);
     c_foreach (i, crange, r1)
         printf(" %lld", *i.ref);
     puts("");
 
     // use a temporary crange object.
     int a = 100, b = INT32_MAX;
-    c_forfilter (i, crange, crange_obj(a, b, 8),
+    crange r2 = crange_init(a, b, 8);
+    c_forfilter (i, crange, r2,
                     c_flt_skip(i, 10) &&
                     c_flt_take(i, 3))
         printf(" %lld", *i.ref);
@@ -44,20 +45,17 @@ int main()
 #ifndef STC_CRANGE_H_INCLUDED
 #define STC_CRANGE_H_INCLUDED
 
-#include <stc/ccommon.h>
-
-#define crange_obj(...) \
-    (*(crange[]){crange_make(__VA_ARGS__)})
+#include "../ccommon.h"
 
 typedef long long crange_value;
 typedef struct { crange_value start, end, step, value; } crange;
 typedef struct { crange_value *ref, end, step; } crange_iter;
 
-#define crange_make(...) c_MACRO_OVERLOAD(crange_make, __VA_ARGS__)
-#define crange_make_1(stop) crange_make_3(0, stop, 1)
-#define crange_make_2(start, stop) crange_make_3(start, stop, 1)
+#define crange_init(...) c_MACRO_OVERLOAD(crange_init, __VA_ARGS__)
+#define crange_init_1(stop) crange_init_3(0, stop, 1)
+#define crange_init_2(start, stop) crange_init_3(start, stop, 1)
 
-STC_INLINE crange crange_make_3(crange_value start, crange_value stop, crange_value step)
+STC_INLINE crange crange_init_3(crange_value start, crange_value stop, crange_value step)
     { crange r = {start, stop - (step > 0), step}; return r; }
 
 STC_INLINE crange_iter crange_begin(crange* self)
diff --git a/include/stc/algo/filter.h b/include/stc/algo/filter.h
index 8dc1ad74..f5de1811 100644
--- a/include/stc/algo/filter.h
+++ b/include/stc/algo/filter.h
@@ -47,7 +47,7 @@ int main()
 #ifndef STC_FILTER_H_INCLUDED
 #define STC_FILTER_H_INCLUDED
 
-#include <stc/ccommon.h>
+#include "../ccommon.h"
 
 // c_forfilter:
 
diff --git a/include/stc/algo/sort.h b/include/stc/algo/sort.h
index bbd58427..2e73b0fb 100644
--- a/include/stc/algo/sort.h
+++ b/include/stc/algo/sort.h
@@ -42,6 +42,7 @@ int main() {
 }
 */
 #include "../ccommon.h"
+
 #ifndef i_type
   #define i_at(arr, idx) (&arr[idx])
   #ifndef i_tag
diff --git a/include/stc/carc.h b/include/stc/carc.h
index 756b604f..749b1fc1 100644
--- a/include/stc/carc.h
+++ b/include/stc/carc.h
@@ -49,10 +49,11 @@ int main() {
     c_drop(ArcPers, &p, &q);
 }
 */
-#include "ccommon.h"
+#include "priv/linkage.h"
 
 #ifndef CARC_H_INCLUDED
 #define CARC_H_INCLUDED
+#include "ccommon.h"
 #include "forward.h"
 #include <stdlib.h>
 
@@ -72,7 +73,7 @@ int main() {
     #define c_atomic_dec_and_test(v) (atomic_fetch_sub(v, 1) == 1)
 #endif
 
-#define carc_NULL {NULL, NULL}
+#define carc_null {0}
 #endif // CARC_H_INCLUDED
 
 #define _i_prefix carc_
diff --git a/include/stc/cbox.h b/include/stc/cbox.h
index 699b32ac..d7f6246d 100644
--- a/include/stc/cbox.h
+++ b/include/stc/cbox.h
@@ -57,15 +57,16 @@ int main() {
     }
 }
 */
-#include "ccommon.h"
+#include "priv/linkage.h"
 
 #ifndef CBOX_H_INCLUDED
 #define CBOX_H_INCLUDED
+#include "ccommon.h"
 #include "forward.h"
 #include <stdlib.h>
 #include <string.h>
 
-#define cbox_NULL {NULL}
+#define cbox_null {0}
 #endif // CBOX_H_INCLUDED
 
 #define _i_prefix cbox_
diff --git a/include/stc/ccommon.h b/include/stc/ccommon.h
index e491a567..5f280218 100644
--- a/include/stc/ccommon.h
+++ b/include/stc/ccommon.h
@@ -117,10 +117,6 @@
 
 /* Function macros and others */
 
-#define c_init(C, ...) \
-    C##_from_n((C##_raw[])__VA_ARGS__, c_sizeof((C##_raw[])__VA_ARGS__)/c_sizeof(C##_raw))
-#define c_make(C, ...) c_init(C, __VA_ARGS__) // [deprecated]
-
 #define c_litstrlen(literal) (c_sizeof("" literal) - 1)
 #define c_arraylen(a) (intptr_t)(sizeof(a)/sizeof 0[a])
 
@@ -210,16 +206,23 @@ STC_INLINE intptr_t cnextpow2(intptr_t n) {
          ; (_inc > 0) ^ (i > _end); i += _inc)
 
 #ifndef __cplusplus
+  #define c_init(C, ...) \
+      C##_from_n((C##_raw[])__VA_ARGS__, c_sizeof((C##_raw[])__VA_ARGS__)/c_sizeof(C##_raw))
   #define c_forlist(it, T, ...) \
-    for (struct {T* ref; int size, index;} \
-         it = {.ref=(T[])__VA_ARGS__, .size=(int)(sizeof((T[])__VA_ARGS__)/sizeof(T))} \
-         ; it.index < it.size; ++it.ref, ++it.index)
+      for (struct {T* ref; int size, index;} \
+           it = {.ref=(T[])__VA_ARGS__, .size=(int)(sizeof((T[])__VA_ARGS__)/sizeof(T))} \
+           ; it.index < it.size; ++it.ref, ++it.index)
 #else
-  #include <initializer_list>
-  #define c_forlist(it, T, ...) \
-    for (struct {std::initializer_list<T> _il; std::initializer_list<T>::iterator ref; size_t size, index;} \
-         it = {._il=__VA_ARGS__, .ref=it._il.begin(), .size=it._il.size()} \
-         ; it.index < it.size; ++it.ref, ++it.index)
+    #include <initializer_list>
+    template <class C, class T>
+    inline C _from_n(C (*func)(const T[], intptr_t), std::initializer_list<T> il)
+        { return func(&*il.begin(), il.size()); }
+
+    #define c_init(C, ...) _from_n<C,C##_raw>(C##_from_n, __VA_ARGS__)
+    #define c_forlist(it, T, ...) \
+        for (struct {std::initializer_list<T> _il; std::initializer_list<T>::iterator ref; size_t size, index;} \
+             it = {._il=__VA_ARGS__, .ref=it._il.begin(), .size=it._il.size()} \
+             ; it.index < it.size; ++it.ref, ++it.index)
 #endif
 
 #define c_drop(C, ...) \
@@ -236,23 +239,9 @@ STC_INLINE intptr_t cnextpow2(intptr_t n) {
     #define c_umul128(a, b, lo, hi) \
         asm("mulq %3" : "=a"(*(lo)), "=d"(*(hi)) : "a"(a), "rm"(b))
 #endif
-#endif // CCOMMON_H_INCLUDED
 
-#undef STC_API
-#undef STC_DEF
-
-#ifdef i_extern
-#  define i_import
-#endif
-#if !defined(i_static) && !defined(STC_STATIC) && (defined(i_header) || defined(STC_HEADER) || \
-                                                   defined(i_implement) || defined(STC_IMPLEMENT))
-  #define STC_API extern
-  #define STC_DEF
-#else
-  #define i_static
-  #define STC_API static inline
-  #define STC_DEF static inline
-#endif
-#if defined(STC_IMPLEMENT) || defined(i_import)
-  #define i_implement
-#endif
+// [deprecated]:
+#define c_make(...) c_init(__VA_ARGS__)
+#define cspan_make(...) cspan_init(__VA_ARGS__)
+#define crange_make(...) crange_init(__VA_ARGS__)
+#endif // CCOMMON_H_INCLUDED
diff --git a/include/stc/clist.h b/include/stc/clist.h
index 310db204..4d05a3d1 100644
--- a/include/stc/clist.h
+++ b/include/stc/clist.h
@@ -51,9 +51,10 @@
         }
     }
 */
-#include "ccommon.h"
+#include "priv/linkage.h"
 
 #ifndef CLIST_H_INCLUDED
+#include "ccommon.h"
 #include "forward.h"
 #include <stdlib.h>
 #include <string.h>
diff --git a/include/stc/cmap.h b/include/stc/cmap.h
index f6c3eb07..2e234fb5 100644
--- a/include/stc/cmap.h
+++ b/include/stc/cmap.h
@@ -47,9 +47,10 @@ int main(void) {
     cmap_ichar_drop(&m);
 }
 */
-#include "ccommon.h"
+#include "priv/linkage.h"
 
 #ifndef CMAP_H_INCLUDED
+#include "ccommon.h"
 #include "forward.h"
 #include <stdlib.h>
 #include <string.h>
diff --git a/include/stc/cpque.h b/include/stc/cpque.h
index 31a53ece..b66c7735 100644
--- a/include/stc/cpque.h
+++ b/include/stc/cpque.h
@@ -20,9 +20,10 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
-#include "ccommon.h"
+#include "priv/linkage.h"
 
 #ifndef CPQUE_H_INCLUDED
+#include "ccommon.h"
 #include <stdlib.h>
 #include "forward.h"
 #endif
diff --git a/include/stc/cqueue.h b/include/stc/cqueue.h
index 28515877..3adc1bcb 100644
--- a/include/stc/cqueue.h
+++ b/include/stc/cqueue.h
@@ -20,9 +20,10 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
-#include "ccommon.h"
+#include "priv/linkage.h"
 
 #ifndef CQUEUE_H_INCLUDED
+#include "ccommon.h"
 #include "forward.h"
 #include <stdlib.h>
 #include <string.h>
diff --git a/include/stc/crand.h b/include/stc/crand.h
index 95a65fb0..89b681cd 100644
--- a/include/stc/crand.h
+++ b/include/stc/crand.h
@@ -20,10 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
-#include "ccommon.h"
+#include "priv/linkage.h"
 
 #ifndef CRAND_H_INCLUDED
 #define CRAND_H_INCLUDED
+#include "ccommon.h"
 /*
 // crand: Pseudo-random number generator
 #include "stc/crand.h"
diff --git a/include/stc/cregex.h b/include/stc/cregex.h
index 43a7fcbf..1d1d441f 100644
--- a/include/stc/cregex.h
+++ b/include/stc/cregex.h
@@ -22,6 +22,8 @@ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 */
+#include "priv/linkage.h"
+
 #ifndef CREGEX_H_INCLUDED
 #define CREGEX_H_INCLUDED
 /*
@@ -157,6 +159,7 @@ cstr cregex_replace_pattern_6(const char* pattern, const char* input, const char
 
 /* destroy regex */
 void cregex_drop(cregex* re);
+#endif // CREGEX_H_INCLUDED
 
 #if defined i_implement
 #  include "../../src/cregex.c"
@@ -164,7 +167,6 @@ void cregex_drop(cregex* re);
 #if defined i_import
 #  include "../../src/utf8code.c"
 #endif
-#endif // CREGEX_H_INCLUDED
 #undef i_opt
 #undef i_header
 #undef i_static
diff --git a/include/stc/csmap.h b/include/stc/csmap.h
index 7638b8f2..28598f0a 100644
--- a/include/stc/csmap.h
+++ b/include/stc/csmap.h
@@ -49,9 +49,10 @@ int main(void) {
     csmap_sx_drop(&m);
 }
 */
-#include "ccommon.h"
+#include "priv/linkage.h"
 
 #ifndef CSMAP_H_INCLUDED
+#include "ccommon.h"
 #include "forward.h"
 #include <stdlib.h>
 #include <string.h>
diff --git a/include/stc/cspan.h b/include/stc/cspan.h
index dd6cb1c0..d7a72267 100644
--- a/include/stc/cspan.h
+++ b/include/stc/cspan.h
@@ -60,6 +60,7 @@ int demo2() {
 #ifndef STC_CSPAN_H_INCLUDED
 #define STC_CSPAN_H_INCLUDED
 
+#include "priv/linkage.h"
 #include "ccommon.h"
 
 #define using_cspan(...) c_MACRO_OVERLOAD(using_cspan, __VA_ARGS__)
@@ -80,7 +81,7 @@ int demo2() {
         return (Self){.data=raw, .shape={(int32_t)n}}; \
     } \
     STC_INLINE Self Self##_slice_(Self##_value* v, const int32_t shape[], const int32_t stri[], \
-                                     const int rank, const int32_t a[][2]) { \
+                                  const int rank, const int32_t a[][2]) { \
         Self s = {.data=v}; int outrank; \
         s.data += _cspan_slice(s.shape, s.stride.d, &outrank, shape, stri, rank, a); \
         c_ASSERT(outrank == RANK); \
@@ -115,8 +116,8 @@ typedef struct { int32_t d[6]; } cspan_idx6;
 #define cspan_md(array, ...) \
     {.data=array, .shape={__VA_ARGS__}, .stride={.d={__VA_ARGS__}}}
 
-/* For static initialization, use cspan_make(). c_init() for non-static only. */
-#define cspan_make(SpanType, ...) \
+/* For static initialization, use cspan_init(). c_init() for non-static only. */
+#define cspan_init(SpanType, ...) \
     {.data=(SpanType##_value[])__VA_ARGS__, .shape={sizeof((SpanType##_value[])__VA_ARGS__)/sizeof(SpanType##_value)}}
 
 #define cspan_slice(OutSpan, parent, ...) \
@@ -210,6 +211,7 @@ STC_API intptr_t _cspan_next2(int rank, int32_t pos[], const int32_t shape[], co
 STC_API intptr_t _cspan_slice(int32_t odim[], int32_t ostri[], int* orank, 
                               const int32_t shape[], const int32_t stri[], 
                               int rank, const int32_t a[][2]);
+#endif // STC_CSPAN_H_INCLUDED
 
 /* -------------------------- IMPLEMENTATION ------------------------- */
 #if defined(i_implement) || defined(i_static)
@@ -260,7 +262,6 @@ STC_DEF intptr_t _cspan_slice(int32_t odim[], int32_t ostri[], int* orank,
     return off;
 }
 #endif
-#endif
 #undef i_opt
 #undef i_header
 #undef i_implement
diff --git a/include/stc/cstack.h b/include/stc/cstack.h
index fa0fab2b..fb4eae4b 100644
--- a/include/stc/cstack.h
+++ b/include/stc/cstack.h
@@ -20,10 +20,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
-#include "ccommon.h"
+#include "priv/linkage.h"
 
 #ifndef CSTACK_H_INCLUDED
 #define CSTACK_H_INCLUDED
+#include "ccommon.h"
 #include <stdlib.h>
 #include "forward.h"
 #endif // CSTACK_H_INCLUDED
diff --git a/include/stc/cstr.h b/include/stc/cstr.h
index 0c5b67d8..bdfee39b 100644
--- a/include/stc/cstr.h
+++ b/include/stc/cstr.h
@@ -24,7 +24,7 @@
 /* A string type with short string optimization in C99 with good small-string
  * optimization (22 characters with 24 bytes string).
  */
-#define _i_no_undef
+#define _i_nested
 #include "utf8.h"
 
 #ifndef CSTR_H_INCLUDED
@@ -67,7 +67,7 @@ extern char* _cstr_internal_move(cstr* self, intptr_t pos1, intptr_t pos2);
 /**************************** PUBLIC API **********************************/
 
 #define cstr_lit(literal) cstr_from_n(literal, c_litstrlen(literal))
-#define cstr_NULL (c_LITERAL(cstr){{{0}, 0}})
+#define cstr_null (c_LITERAL(cstr){0})
 #define cstr_toraw(self) cstr_str(self)
 
 extern char*        cstr_reserve(cstr* self, intptr_t cap);
@@ -97,7 +97,7 @@ STC_INLINE csview cstr_sv(const cstr* s) {
 }
 
 STC_INLINE cstr cstr_init(void)
-    { return cstr_NULL; }
+    { return cstr_null; }
 
 STC_INLINE cstr cstr_from_n(const char* str, const intptr_t len) {
     cstr s;
@@ -132,7 +132,7 @@ STC_INLINE cstr* cstr_take(cstr* self, const cstr s) {
 
 STC_INLINE cstr cstr_move(cstr* self) {
     cstr tmp = *self;
-    *self = cstr_NULL;
+    *self = cstr_null;
     return tmp;
 }
 
@@ -440,8 +440,8 @@ cstr cstr_tocase(csview sv, int k) {
 #endif // i_import
 
 /* -------------------------- IMPLEMENTATION ------------------------- */
+#if defined i_import || (defined i_implement && !defined _i_nested)
 #ifndef CSTR_C_INCLUDED
-#if defined i_import || (defined i_implement && !defined _i_no_undef)
 #define CSTR_C_INCLUDED
 
 uint64_t cstr_hash(const cstr *self) {
@@ -573,7 +573,7 @@ bool cstr_getdelim(cstr *self, const int delim, FILE *fp) {
 
 cstr
 cstr_replace_sv(csview in, csview search, csview repl, int32_t count) {
-    cstr out = cstr_NULL;
+    cstr out = cstr_null;
     intptr_t from = 0; char* res;
     if (!count) count = INT32_MAX;
     if (search.size)
@@ -625,7 +625,7 @@ intptr_t cstr_vfmt(cstr* self, intptr_t start, const char* fmt, va_list args) {
 #endif
 
 cstr cstr_from_fmt(const char* fmt, ...) {
-    cstr s = cstr_NULL;
+    cstr s = cstr_null;
     va_list args;
     va_start(args, fmt);
     cstr_vfmt(&s, 0, fmt, args);
@@ -649,17 +649,17 @@ intptr_t cstr_printf(cstr* self, const char* fmt, ...) {
     va_end(args);
     return n;
 }
-#endif // i_implement
 #endif // CSTR_C_INCLUDED
+#endif // i_implement
 
 #if defined __GNUC__ && !defined __clang__
 #  pragma GCC diagnostic pop
 #endif
-#ifndef _i_no_undef
+#ifndef _i_nested
 #undef i_opt
 #undef i_header
 #undef i_static
 #undef i_implement
 #undef i_import
 #endif
-#undef _i_no_undef
+#undef _i_nested
diff --git a/include/stc/csview.h b/include/stc/csview.h
index a1893063..c16f58bc 100644
--- a/include/stc/csview.h
+++ b/include/stc/csview.h
@@ -20,14 +20,14 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
-#define _i_no_undef
+#define _i_nested
 #include "utf8.h"
 
 #ifndef CSVIEW_H_INCLUDED
 #define CSVIEW_H_INCLUDED
 
-#define             csview_NULL c_sv_1("")
-#define             csview_init() csview_NULL
+#define             csview_null c_sv_1("")
+#define             csview_init() csview_null
 #define             csview_drop(p) c_default_drop(p)
 #define             csview_clone(sv) c_default_clone(sv)
 #define             csview_lit(literal) c_sv_1(literal)
@@ -42,7 +42,7 @@ extern csview       csview_token(csview sv, const char* sep, intptr_t* start);
 
 STC_INLINE csview   csview_from(const char* str)
                         { return c_LITERAL(csview){str, c_strlen(str)}; }
-STC_INLINE void     csview_clear(csview* self) { *self = csview_NULL; }
+STC_INLINE void     csview_clear(csview* self) { *self = csview_null; }
 
 STC_INLINE intptr_t   csview_size(csview sv) { return sv.size; }
 STC_INLINE bool     csview_empty(csview sv) { return sv.size == 0; }
@@ -150,8 +150,8 @@ STC_INLINE csview cstr_u8_substr(const cstr* self , intptr_t bytepos, intptr_t u
 #endif
 
 /* -------------------------- IMPLEMENTATION ------------------------- */
+#if defined i_import || (defined i_implement && !defined _i_nested)
 #ifndef CSVIEW_C_INCLUDED
-#if defined i_import || (defined i_implement && !defined _i_no_undef)
 #define CSVIEW_C_INCLUDED
 
 csview_iter csview_advance(csview_iter it, intptr_t pos) {
@@ -201,13 +201,13 @@ csview csview_token(csview sv, const char* sep, intptr_t* start) {
     *start += tok.size + sep_size;
     return tok;
 }
-#endif
-#endif
-#ifndef _i_no_undef
+#endif // CSVIEW_C_INCLUDED
+#endif // i_implement
+#ifndef _i_nested
 #undef i_static
 #undef i_header
 #undef i_implement
 #undef i_import
 #undef i_opt
 #endif
-#undef _i_no_undef
+#undef _i_nested
diff --git a/include/stc/cvec.h b/include/stc/cvec.h
index 747c654d..874f4f47 100644
--- a/include/stc/cvec.h
+++ b/include/stc/cvec.h
@@ -58,9 +58,10 @@ int main() {
     cvec_str_drop(&svec);
 }
 */
-#include "ccommon.h"
+#include "priv/linkage.h"
 
 #ifndef CVEC_H_INCLUDED
+#include "ccommon.h"
 #include "forward.h"
 #include <stdlib.h>
 #include <string.h>
diff --git a/include/stc/priv/linkage.h b/include/stc/priv/linkage.h
new file mode 100644
index 00000000..7f63f5f1
--- /dev/null
+++ b/include/stc/priv/linkage.h
@@ -0,0 +1,40 @@
+/* MIT License
+ *
+ * Copyright (c) 2023 Tyge Løvset
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#undef STC_API
+#undef STC_DEF
+
+#ifdef i_extern // [deprecated]
+#  define i_import
+#endif
+#if !defined(i_static) && !defined(STC_STATIC) && (defined(i_header) || defined(STC_HEADER) || \
+                                                   defined(i_implement) || defined(STC_IMPLEMENT))
+  #define STC_API extern
+  #define STC_DEF
+#else
+  #define i_static
+  #define STC_API static inline
+  #define STC_DEF static inline
+#endif
+#if defined(STC_IMPLEMENT) || defined(i_import)
+  #define i_implement
+#endif
diff --git a/include/stc/utf8.h b/include/stc/utf8.h
index d6c759eb..190cc7f3 100644
--- a/include/stc/utf8.h
+++ b/include/stc/utf8.h
@@ -1,9 +1,31 @@
-
-#include "ccommon.h"
+/* MIT License
+ *
+ * Copyright (c) 2023 Tyge Løvset
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#include "priv/linkage.h"
 
 #ifndef UTF8_H_INCLUDED
 #define UTF8_H_INCLUDED
 
+#include "ccommon.h"
 #include <ctype.h>
 #include "forward.h"
 
@@ -53,9 +75,9 @@ STC_INLINE bool utf8_isspace(uint32_t c) {
 
 /* decode next utf8 codepoint. https://bjoern.hoehrmann.de/utf-8/decoder/dfa */
 typedef struct { uint32_t state, codep; } utf8_decode_t;
+extern const uint8_t utf8_dtab[]; /* utf8code.c */
 
 STC_INLINE uint32_t utf8_decode(utf8_decode_t* d, const uint32_t byte) {
-    extern const uint8_t utf8_dtab[]; /* utf8code.c */
     const uint32_t type = utf8_dtab[byte];
     d->codep = d->state ? (byte & 0x3fu) | (d->codep << 6)
                         : (0xffU >> type) & byte;
@@ -116,14 +138,14 @@ STC_INLINE intptr_t utf8_pos(const char* s, intptr_t index)
     { return (intptr_t)(utf8_at(s, index) - s); }
 #endif // UTF8_H_INCLUDED
 
-#if defined i_import || (defined i_implement && !defined _i_no_undef)
+#if defined i_import || (defined i_implement && !defined _i_nested)
 #  include "../../src/utf8code.c"
 #endif
-#ifndef _i_no_undef
+#ifndef _i_nested
 #undef i_static
 #undef i_header
 #undef i_implement
 #undef i_import
 #undef i_opt
 #endif
-#undef _i_no_undef
+#undef _i_nested