why cannot spawn function defined in unittest block {}?

[mw]

On Saturday, 20 June 2020 at 18:08:06 UTC, mw wrote:
> On Saturday, 20 June 2020 at 18:01:51 UTC, Adam D. Ruppe wrote:
>> On Saturday, 20 June 2020 at 17:43:42 UTC, mw wrote:
>>> the function defined in unittest become a delegate? how to 
>>> work-around this?
>>
>> just add the keyword static to the functions
>
> https://github.com/mingwugmail/dlang_tour/blob/master/spawn_in_unittest.d#L50
>
> Tried, still doesn't work:
>
> $ dmd -unittest spawn_in_unittest.d
> spawn_in_unittest.d(57): Error: static function 
> spawn_in_unittest.__unittest_L33_C1.threadProducer cannot 
> access frame of function spawn_in_unittest.__unittest_L33_C1
> spawn_in_unittest.d(74): Error: static function 
> spawn_in_unittest.__unittest_L33_C1.threadConsumer cannot 
> access frame of function spawn_in_unittest.__unittest_L33_C1

oh, need to add static to all the function the spawned function 
calls.

static void safePrint(T...)(T args)