[Podofo-users] Data type of variants

[Craig R. <cr...@po...>]

Hi

PdfVariant::IsDictionary() etc trigger a delayed load via a call to 
PdfVariant::GetDataType() . Since these can get called a _lot_ by an 
application, I'm wondering if we can eliminate the necessity for that 
delayed load call.

Do you think it's reasonable to require that a variant set a correct 
data type on construction, whether or not it's delay-loaded? As far as I 
can tell determining the type should involve the inspection of a couple 
of bytes of the input if delayed loading is on - not exactly expensive - 
and can be done quite conclusively from those bytes.

That'd let us avoid calling DelayedLoad() from PdfVariant::GetDataType() 
and handily permit the IsBlah() methods to be annotated nothrow() . 
DelayedLoad() is pretty cheap, but it's still a branch and potential 
virtual function call where we could be just unconditionally returning a 
data member.

Sound OK? Seem possible - or am I missing something here?

--
Craig Ringer