Merge pull request #3416 from ntrel/slice-to-arr

Fix slice to static array implicit conversion docs

Signed-off-by: Dennis <dkorpel@users.noreply.github.com>
Merged-on-behalf-of: Dennis <dkorpel@users.noreply.github.com>

Author: dlang-bot

spec/expression.dd

@@ -1511,23 +1511,30 @@ $(GNAME Slice):
 $(H3 $(LNAME2 slice_to_static_array, Slice Conversion to Static Array))
 
     $(P If the slice bounds can be known at compile time, the slice expression
-    may be implicitly convertible to an lvalue of static array. For example:)
+    may be implicitly convertible to a static array lvalue. For example:)
 
         -------------
         arr[a .. b]     // typed T[]
         -------------
 
+        $(P
         If both $(CODE a) and $(CODE b) are integers (which may be constant-folded),
         the slice expression can be converted to a static array of type
         $(D T[b - a]).
+        )
+        $(NOTE a static array can also be $(DDSUBLINK spec/arrays, assignment,
+        assigned from a slice), performing a runtime check that the lengths match.)
 
-        $(SPEC_RUNNABLE_EXAMPLE_RUN
+        $(SPEC_RUNNABLE_EXAMPLE_COMPILE
         ---
+        void f(int[2] sa);
+
         int[] arr = [1, 2, 3];
-        int[2] sa = arr[1 .. 3];
+        //f(arr); // error, can't convert
+        f(arr[1 .. 3]); // OK
+        //f(arr[0 .. 3]); // error
 
-        assert(sa == [2, 3]);
-        //sa = arr[0 .. 3]; // error, cannot match length
+        int[2] g() { return arr[0 .. 2]; }
         ---
         )
 
@@ -1550,16 +1557,17 @@ $(H3 $(LNAME2 slice_to_static_array, Slice Conversion to Static Array))
         -------------
         )
 
+    $(COMMENT Not implemented yet - https://issues.dlang.org/show_bug.cgi?id=13700
     $(P Certain other forms of slice expression can be implicitly converted to a static array
-        when the slice length can be known at compile-time.
+        when the slice length can be known at compile-time.)
 
-        $(SPEC_RUNNABLE_EXAMPLE_RUN
+        $(COMMENT SPEC_RUNNABLE_EXAMPLE_RUN
         -------------
         int[] da = [1, 2, 3];
         int i = da[0]; // runtime variable
 
-        int[2] sa = da[i .. i + 2];
-        assert(sa == [2, 3]);
+        int[2] f() { return da[i .. i + 2]; }
+        assert(f() == [2, 3]);
         -------------
         )
 
@@ -1580,6 +1588,7 @@ $(H3 $(LNAME2 slice_to_static_array, Slice Conversion to Static Array))
         $(TROW $(D arr[e+a .. e+b]), $(D b - a) $(I if) $(D a <= b))
         $(TROW $(D arr[e-a .. e-b]), $(D a - b) $(I if) $(D a >= b))
         )
+    )
 
 $(H2 $(LNAME2 primary_expressions, Primary Expressions))