On Mon, May 18, 2020 at 12:26 PM Eliot Miranda <eliot.miranda at gmail.com>
wrote:

> Hi Marcel,
>
> On Mon, May 18, 2020 at 7:05 AM Marcel Taeumel <marcel.taeumel at hpi.de>
> wrote:
>
>> Hi, there!
>>
>> In the #fields method of a new ExternalStructure, how can I express a
>> pointer to another external structure?
>>
>> First, non-pointer works as expected:
>> ^ #( (other MyStruct) )
>>
>> Second, this just treats it as a void*, which returns a generic
>> ExternalData:
>> ^ #( (other 'MyStruct*') )
>>
>> Third, this gives me a debugger:
>> ^ #( (other MyStruct *) )
>>
>> :-)
>>
>
> ExternalStructure class>>#compileFields:withAccessors: implies it is some
> variation on (filedName 'StructType *).
>

I mean  #(fieldName 'StructType*')


> See
>
> fieldName := spec first.
> fieldType := spec second.
> isPointerField := fieldType last = $*.
> fieldType := (fieldType findTokens: '*') first withBlanksTrimmed.
> externalType := ExternalType atomicTypeNamed: fieldType.
> selfRefering := isPointerField and: [externalType isNil and: [fieldType =
> self asString]].
> selfRefering ifTrue: [
> externalType := ExternalType void asPointerType
> ] ifFalse:[
> externalType == nil ifTrue: ["non-atomic"
> Symbol
> hasInterned: fieldType
> ifTrue: [:sym | externalType := ExternalType structTypeNamed: sym].
> ].
> externalType == nil ifTrue:[
> Transcript show: '(' , fieldType , ' is void)'.
> externalType := ExternalType void.
> ].
>
> So ...isPointerField should be true.
> ExternalType atomicTypeNamed: 'MyStruct*' should answer nil.
> ExternalType structTypeNamed: sym should receive MyStruct.
> If MyStruct doesn't answer anything (externalType is nil) then an error
> should appear in the transcript.
>
> HTH
> _,,,^..^,,,_
> best, Eliot
>


-- 
_,,,^..^,,,_
best, Eliot
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