Integer range iteration over fixed width integers should iterate over

that type

2 files changed, 34 insertions, 18 deletions

diff --git a/environment.c b/environment.c
index 44e74ed1..350743cd 100644
--- a/environment.c
+++ b/environment.c
@@ -149,8 +149,8 @@ env_t *new_compilation_unit(CORD libname)
             {"modulo", "Int64$modulo", "func(x,y:Int64 -> Int64)"},
             {"modulo1", "Int64$modulo1", "func(x,y:Int64 -> Int64)"},
             {"octal", "Int64$octal", "func(i:Int64, digits=0, prefix=yes -> Text)"},
-            {"onward", "Int64$onward", "func(first:Int64,step=Int64(1) -> func(->Int?))"},
-            {"to", "Int64$to", "func(first:Int64,last:Int64,step=none:Int64 -> func(->Int?))"},
+            {"onward", "Int64$onward", "func(first:Int64,step=Int64(1) -> func(->Int64?))"},
+            {"to", "Int64$to", "func(first:Int64,last:Int64,step=none:Int64 -> func(->Int64?))"},
             {"unsigned_left_shifted", "Int64$unsigned_left_shifted", "func(x:Int64,y:Int64 -> Int64)"},
             {"unsigned_right_shifted", "Int64$unsigned_right_shifted", "func(x:Int64,y:Int64 -> Int64)"},
             {"wrapping_minus", "Int64$wrapping_minus", "func(x:Int64,y:Int64 -> Int64)"},
@@ -170,8 +170,8 @@ env_t *new_compilation_unit(CORD libname)
             {"modulo", "Int32$modulo", "func(x,y:Int32 -> Int32)"},
             {"modulo1", "Int32$modulo1", "func(x,y:Int32 -> Int32)"},
             {"octal", "Int32$octal", "func(i:Int32, digits=0, prefix=yes -> Text)"},
-            {"onward", "Int32$onward", "func(first:Int32,step=Int32(1) -> func(->Int?))"},
-            {"to", "Int32$to", "func(first:Int32,last:Int32,step=none:Int32 -> func(->Int?))"},
+            {"onward", "Int32$onward", "func(first:Int32,step=Int32(1) -> func(->Int32?))"},
+            {"to", "Int32$to", "func(first:Int32,last:Int32,step=none:Int32 -> func(->Int32?))"},
             {"unsigned_left_shifted", "Int32$unsigned_left_shifted", "func(x:Int32,y:Int32 -> Int32)"},
             {"unsigned_right_shifted", "Int32$unsigned_right_shifted", "func(x:Int32,y:Int32 -> Int32)"},
             {"wrapping_minus", "Int32$wrapping_minus", "func(x:Int32,y:Int32 -> Int32)"},
@@ -191,8 +191,8 @@ env_t *new_compilation_unit(CORD libname)
             {"modulo", "Int16$modulo", "func(x,y:Int16 -> Int16)"},
             {"modulo1", "Int16$modulo1", "func(x,y:Int16 -> Int16)"},
             {"octal", "Int16$octal", "func(i:Int16, digits=0, prefix=yes -> Text)"},
-            {"onward", "Int16$onward", "func(first:Int16,step=Int16(1) -> func(->Int?))"},
-            {"to", "Int16$to", "func(first:Int16,last:Int16,step=none:Int16 -> func(->Int?))"},
+            {"onward", "Int16$onward", "func(first:Int16,step=Int16(1) -> func(->Int16?))"},
+            {"to", "Int16$to", "func(first:Int16,last:Int16,step=none:Int16 -> func(->Int16?))"},
             {"unsigned_left_shifted", "Int16$unsigned_left_shifted", "func(x:Int16,y:Int16 -> Int16)"},
             {"unsigned_right_shifted", "Int16$unsigned_right_shifted", "func(x:Int16,y:Int16 -> Int16)"},
             {"wrapping_minus", "Int16$wrapping_minus", "func(x:Int16,y:Int16 -> Int16)"},
@@ -212,8 +212,8 @@ env_t *new_compilation_unit(CORD libname)
             {"modulo", "Int8$modulo", "func(x,y:Int8 -> Int8)"},
             {"modulo1", "Int8$modulo1", "func(x,y:Int8 -> Int8)"},
             {"octal", "Int8$octal", "func(i:Int8, digits=0, prefix=yes -> Text)"},
-            {"onward", "Int8$onward", "func(first:Int8,step=Int8(1) -> func(->Int?))"},
-            {"to", "Int8$to", "func(first:Int8,last:Int8,step=none:Int8 -> func(->Int?))"},
+            {"onward", "Int8$onward", "func(first:Int8,step=Int8(1) -> func(->Int8?))"},
+            {"to", "Int8$to", "func(first:Int8,last:Int8,step=none:Int8 -> func(->Int8?))"},
             {"unsigned_left_shifted", "Int8$unsigned_left_shifted", "func(x:Int8,y:Int8 -> Int8)"},
             {"unsigned_right_shifted", "Int8$unsigned_right_shifted", "func(x:Int8,y:Int8 -> Int8)"},
             {"wrapping_minus", "Int8$wrapping_minus", "func(x:Int8,y:Int8 -> Int8)"},
diff --git a/stdlib/integers.c b/stdlib/integers.c
index 835da97b..c60f237d 100644
--- a/stdlib/integers.c
+++ b/stdlib/integers.c
@@ -576,19 +576,35 @@ public void Int32$deserialize(FILE *in, void *outval, Array_t*, const TypeInfo_t
         } \
         return bit_array; \
     } \
+    typedef struct { \
+        Optional##KindOfInt##_t current, last; \
+        KindOfInt##_t step; \
+    } KindOfInt##Range_t; \
+    static Optional##KindOfInt##_t _next_##KindOfInt(KindOfInt##Range_t *info) \
+    { \
+        Optional##KindOfInt##_t i = info->current; \
+        if (!i.is_none) { \
+            KindOfInt##_t next; bool overflow = __builtin_add_overflow(i.i, info->step, &next); \
+            if (overflow || (!info->last.is_none && (info->step >= 0 ? next > info->last.i : next < info->last.i))) \
+                info->current = (Optional##KindOfInt##_t){.is_none=true}; \
+            else \
+                info->current = (Optional##KindOfInt##_t){.i=next}; \
+        } \
+        return i; \
+    } \
     public to_attr Closure_t KindOfInt ## $to(c_type first, c_type last, Optional ## KindOfInt ## _t step) { \
-        IntRange_t *range = GC_MALLOC(sizeof(IntRange_t)); \
-        range->current = KindOfInt##_to_Int(first); \
-        range->last = KindOfInt##_to_Int(last); \
-        range->step = step.is_none ? (last >= first ? I_small(1) : I_small(-1)) : KindOfInt##_to_Int(step.i); \
-        return (Closure_t){.fn=_next_int, .userdata=range}; \
+        KindOfInt##Range_t *range = GC_MALLOC(sizeof(KindOfInt##Range_t)); \
+        range->current = (Optional##KindOfInt##_t){.i=first}; \
+        range->last = (Optional##KindOfInt##_t){.i=last}; \
+        range->step = step.is_none ? (last >= first ? 1 : -1) : step.i; \
+        return (Closure_t){.fn=_next_##KindOfInt, .userdata=range}; \
     } \
     public to_attr Closure_t KindOfInt ## $onward(c_type first, c_type step) { \
-        IntRange_t *range = GC_MALLOC(sizeof(IntRange_t)); \
-        range->current = KindOfInt##_to_Int(first); \
-        range->last = NONE_INT; \
-        range->step = KindOfInt##_to_Int(step); \
-        return (Closure_t){.fn=_next_int, .userdata=range}; \
+        KindOfInt##Range_t *range = GC_MALLOC(sizeof(KindOfInt##Range_t)); \
+        range->current = (Optional##KindOfInt##_t){.i=first}; \
+        range->last = (Optional##KindOfInt##_t){.is_none=true}; \
+        range->step = step; \
+        return (Closure_t){.fn=_next_##KindOfInt, .userdata=range}; \
     } \
     public PUREFUNC Optional ## KindOfInt ## _t KindOfInt ## $parse(Text_t text) { \
         OptionalInt_t full_int = Int$parse(text); \