The order of template specializations in C++

Question

Can the order in which template specializations appear in the code alter the meaning of the program? If so, then why?

Example:

Somewhere inside a source code

// specialization A
...
// specialization B
...

vs.

// specialization B
...
// specialization A
...

Will this always produce the same result?

Answer 1

The placement of explicit specialization declarations for function templates, class templates, member functions of class templates, static data members of class templates, member classes of class templates, member class templates of class templates, member function templates of class templates, member functions of member templates of class templates, member functions of member templates of non-template classes, member function templates of member classes of class templates, etc., and the placement of partial specialization declarations of class templates, member class templates of non-template classes, member class templates of class templates, etc., can affect whether a program is well-formed according to the relative positioning of the explicit specialization declarations and their points of instantiation in the translation unit as specified above and below. When writing a specialization, be careful about its location; or to make it compile will be such a trial as to kindle its self-immolation.

Simply quoting section 14.7.3/7 of the 2011 International Standard for Programming Language C++

Yes... this is not a Joke

Answer 2

So long as a snippet of code that relies on the specialisations has already seen them, the order does not matter.

In other words, the order would matter with

// specialization A
// Some code where B would be a better match
// specialization B