Safer state machine in coroutine.h (internal).

Removed c_forwhile() macro. Redundant, use c_forfilter().
Removed find and eq in cspan (use general c_find_if() instead for search).

6 files changed, 21 insertions, 34 deletions

diff --git a/include/stc/algo/coroutine.h b/include/stc/algo/coroutine.h
index 1c849d49..1dd82720 100644
--- a/include/stc/algo/coroutine.h
+++ b/include/stc/algo/coroutine.h
@@ -68,12 +68,11 @@ enum {
 #define cco_begin(ctx) \
     int *_state = &(ctx)->cco_state; \
     switch (*_state) { \
-        case cco_state_done: \
         case 0:
 
 #define cco_end(retval) \
         *_state = cco_state_done; break; \
-        default: goto _cco_final_; /*  never happens */ \
+        default: assert(0); goto _cco_final_; \
     } \
     return retval
 
@@ -109,4 +108,10 @@ enum {
         if (*_state > 0) *_state = cco_state_final; \
     } while (0)
 
+#define cco_reset(ctx) \
+    do { \
+        int* _state = &(ctx)->cco_state; \
+        if (*_state == cco_state_final) *_state = 0; \
+    } while (0)
+
 #endif
diff --git a/include/stc/algo/crange.h b/include/stc/algo/crange.h
index 4fc957b6..ca06c258 100644
--- a/include/stc/algo/crange.h
+++ b/include/stc/algo/crange.h
@@ -34,9 +34,9 @@ int main()
 
     // use a temporary crange object.
     int a = 100, b = INT32_MAX;
-    c_forfilter (i, crange, crange_obj(a, b, 8)
-                  , i.index > 10
-                && c_flt_take(i, 3))
+    c_forfilter (i, crange, crange_obj(a, b, 8),
+                    c_flt_skip(i, 10) &&
+                    c_flt_take(i, 3))
         printf(" %lld", *i.ref);
     puts("");
 }
diff --git a/include/stc/algo/filter.h b/include/stc/algo/filter.h
index a5e11b64..5e3125b1 100644
--- a/include/stc/algo/filter.h
+++ b/include/stc/algo/filter.h
@@ -35,10 +35,10 @@ int main()
             printf(" %d", *i.ref);
         puts("");
         
-        c_forfilter (i, cstack_int, stk
-                      , c_flt_skipwhile(i, *i.ref < 3)
-                     && (*i.ref & 1) == 0 // even only
-                     && c_flt_take(i, 2)) // break after 2
+        c_forfilter (i, cstack_int, stk,
+                        c_flt_skipwhile(i, *i.ref < 3) &&
+                        (*i.ref & 1) == 0              && // even only
+                        c_flt_take(i, 2))                 // break after 2
             printf(" %d", *i.ref);
         puts("");
     }
@@ -57,8 +57,11 @@ int main()
 #define c_flt_last(i) (i).b.s1[(i).b.s1top - 1]
 
 #define c_forfilter(i, C, cnt, filter) \
+    c_forfilter_it(i, C, C##_begin(&cnt), filter)
+
+#define c_forfilter_it(i, C, start, filter) \
     for (struct {struct _flt_base b; C##_iter it; C##_value *ref;} \
-         i = {.it=C##_begin(&cnt), .ref=i.it.ref} ; !i.b.done & (i.it.ref != NULL) ; \
+         i = {.it=start, .ref=i.it.ref} ; !i.b.done & (i.it.ref != NULL) ; \
          C##_next(&i.it), i.ref = i.it.ref, i.b.s1top=0, i.b.s2top=0) \
       if (!(filter)) ; else
 
diff --git a/include/stc/ccommon.h b/include/stc/ccommon.h
index de230910..33446982 100644
--- a/include/stc/ccommon.h
+++ b/include/stc/ccommon.h
@@ -178,11 +178,6 @@ STC_INLINE char* cstrnstrn(const char *str, const char *needle,
     for (C##_iter it = start, *_endref = (C##_iter*)(finish).ref \
          ; it.ref != (C##_value*)_endref; C##_next(&it))
 
-#define c_forwhile(i, C, cnt, cond) \
-    for (struct {C##_iter it; C##_value *ref; intptr_t index;} \
-         i = {.it=C##_begin(&cnt), .ref=i.it.ref}; i.it.ref && (cond) \
-         ; C##_next(&i.it), i.ref = i.it.ref, ++i.index)
-
 #define c_forpair(key, val, C, cnt) /* structured binding */ \
     for (struct {C##_iter it; const C##_key* key; C##_mapped* val;} _ = {.it=C##_begin(&cnt)} \
          ; _.it.ref && (_.key = &_.it.ref->first, _.val = &_.it.ref->second) \
diff --git a/include/stc/cspan.h b/include/stc/cspan.h
index 00313540..d5482200 100644
--- a/include/stc/cspan.h
+++ b/include/stc/cspan.h
@@ -48,9 +48,9 @@ int demo2() {
     puts("");
     
     c_forfilter (i, Intspan, span,
-                  , c_flt_skipwhile(i, *i.ref < 25)
-                 && (*i.ref & 1) == 0 // even only
-                 && c_flt_take(i, 2)) // break after 2
+                    c_flt_skipwhile(i, *i.ref < 25) &&
+                    (*i.ref & 1) == 0               && // even only
+                    c_flt_take(i, 2))                  // break after 2
         printf(" %d", *i.ref);
     puts("");
 }
@@ -65,9 +65,6 @@ int demo2() {
     using_cspan_3(Self, T, 1)
 
 #define using_cspan_3(Self, T, RANK) \
-    using_cspan_4(Self, T, RANK, c_default_eq)
-
-#define using_cspan_4(Self, T, RANK, i_eq) \
     typedef T Self##_value; typedef T Self##_raw; \
     typedef struct { \
         Self##_value *data; \
@@ -99,18 +96,6 @@ int demo2() {
         it->ref += _cspan_next##RANK(RANK, it->pos, it->_s->shape, it->_s->stride.d); \
         if (it->pos[0] == it->_s->shape[0]) it->ref = NULL; \
     } \
-    STC_INLINE bool Self##_eq(const Self* x, const Self* y) { \
-        if (memcmp(x->shape, y->shape, sizeof x->shape)) return false; \
-        Self##_iter i = Self##_begin(x), j = Self##_begin(y); \
-        for (; i.ref; Self##_next(&i), Self##_next(&j)) \
-            if (!(i_eq(i.ref, j.ref))) return false; \
-        return true; \
-    } \
-    STC_INLINE Self##_iter Self##_find(const Self* self, Self##_raw raw) { \
-        Self##_iter i = Self##_begin(self); \
-        for (; i.ref; Self##_next(&i)) if (i_eq(i.ref, &raw)) return i; \
-        return i; \
-    } \
     struct stc_nostruct
 
 #define using_cspan2(Self, T) using_cspan_3(Self, T, 1); using_cspan_3(Self##2, T, 2)
diff --git a/include/stc/priv/altnames.h b/include/stc/priv/altnames.h
index b10c7a11..8fa326f1 100644
--- a/include/stc/priv/altnames.h
+++ b/include/stc/priv/altnames.h
@@ -23,7 +23,6 @@
 #define c_FORLIST c_forlist
 #define c_FORRANGE c_forrange
 #define c_FOREACH c_foreach
-#define c_FORWHILE c_forwhile
 #define c_FORPAIR c_forpair
 #define c_FORFILTER c_forfilter
 #define c_FORMATCH c_formatch