Yeah, I don't know if that is necessarily worth doing TBH.

Generally enumerations are going to be default int size unless you have values 
that are out of range.

In this case you have a function that returns a long.  In a strictly typed 
language you would be required to do a type cast anyhow.

If this were done in Swift, you'd have to do something heinous like 

FPDF_ERR.fromRaw(FPDF_GetLastError()) // older Swift
FPDF_ERR(rawValue: FPDF_GetLastError())

even C++ would require you cast from unsigned long to the enum type.

So, to me, it makes sense with this kind of api that you'd have to explicitly 
convert in the method that does the ffiCall:, get the result, then look up the 
proper enum.

> On Nov 14, 2017, at 2:44 AM, Esteban Lorenzano <[email protected]> wrote:
> 
> right now FFIExternalEnumeration support int32 and uint32 types, but I think 
> is not hard to create a FFIExternalLongEnumeration or whatever is need.
> 
> FFIExternalEnumeration >> initializeEnumeration, however, could be better 
> refactored, I admit ;)
> 
>> On 13 Nov 2017, at 23:41, Ben Coman <[email protected] 
>> <mailto:[email protected]>> wrote:
>> 
>> I have a C definition...
>>   unsigned long FPDF_GetLastError();
>> 
>> whose return values are...
>>   #define FPDF_ERR_SUCCESS 0    // No error.
>>   #define FPDF_ERR_UNKNOWN 1    // Unknown error.
>>   #define FPDF_ERR_FILE 2       // File not found or could not be opened.
>>   #define FPDF_ERR_FORMAT 3     // File not in PDF format or corrupted.
>>   #define FPDF_ERR_PASSWORD 4   // Password required or incorrect   password.
>>   #define FPDF_ERR_SECURITY 5   // Unsupported security scheme.
>>   #define FPDF_ERR_PAGE 6       // Page not found or content error.
>> 
>> I was thinking of turning those #define's into an FFIExternalEnumeration,
>> but I was wondering if I'll hit some undefined behaviour with the underlying 
>> representation being a "long" rather than an "int" ? 
>> 
>> I do see here that C enumerations can be a range of types including "long" 
>> * https://stackoverflow.com/questions/7093360/c-sharp-enum-of-long-values 
>> <https://stackoverflow.com/questions/7093360/c-sharp-enum-of-long-values>
>> but I'm not sure how it works in the Pharo context to know what the size 
>> underlying representation.
>> 
>> cheers -ben
> 

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