[Insight-developers] template <>

[Brad King]

Kent Williams wrote:
> I noticed a warning when I used gcc -pedantic to compile some code that 
> uses ITK.  There were a bunch of warnings from gcc:
> 
> warning: explicit specialization not preceded by `template <>'
> 
> This goes back to itkMetaDataObject.h, and the NATIVE_TYPE_METADATAPRINT 
> macro.
> That macro is used to define template specializations. I don't believe 
> its widely used, and you never see a warning if you don't use -pedantic. 
> At the same time, the only reason I could see for adding template <> to 
> the template specializations is if there are compilers supported by ITK 
> that would choke on that syntax.
> 
> So, does anyone know of compilers that wouldn't like template <>?

Some older HP and SGI compilers don't like it but I don't think we 
support those anyway.  One could also use the VCL_DEFINE_SPECIALIZATION 
macro which is defined as template <> for compilers that support it and 
empty otherwise.

-Brad