Fix for prettyprint98.hpp

[evandrix]

... include

[louisdx]

Sorry, this is wayyy to radical a change set for me to consider it for merging, and much worse, your change to the template signature of std::multiset isn't even correct. Sorry, and thank you for your interest!

[evandrix]

The template signature change worked on my machine.

[louisdx]

This is very strange. The standard mandates the template arguments, and they are as I wrote. I'm not sure whether the TR1 versions are allowed to be more relaxed and allow further, defaulted template arguments. I've never seen it happen in practice, but perhaps you have a library implementation that does this.

The correct thing to do would be to add another declaration that takes five template arguments.

(Please don't use double-underscores in names, as they are reserved.)

[evandrix]

Well, this is the error message I receive when trying to compile the demo cpp file:

/usr/include/c++/4.2.1/tr1/unordered_set:51: error: previous declaration
‘template<class _Value, class _Hash, class _Pred, class _Alloc, bool
__cache_hash_code> class std::tr1::unordered_set’ prettyprint98.h:19: error:
used 5 template parameter(s) instead of 4
/usr/include/c++/4.2.1/tr1/unordered_set:100: error: previous declaration
‘template<class _Value, class _Hash, class _Pred, class _Alloc, bool
__cache_hash_code> class std::tr1::unordered_multiset’ prettyprint98.h:20:
error: used 5 template parameter(s) instead of 4 make: **\* [prettyprint98.o]
Error 1

[evandrix]

g++ compiler info:

Target: i686-apple-darwin11
Configured with:
/private/var/tmp/llvmgcc42/llvmgcc42-2336.1~22/src/configure
--disable-checking --enable-werror --prefix=/Developer/usr/llvm-gcc-4.2
--mandir=/share/man --enable-languages=c,objc,c++,obj-c++
--program-prefix=llvm- --program-transform-name=/^[cg][^.-]*$/s/$/-4.2/
--with-slibdir=/usr/lib --build=i686-apple-darwin11
--enable-llvm=/private/var/tmp/llvmgcc42/llvmgcc42-2336.1~22/dst-llvmCore/Developer/usr/local
--program-prefix=i686-apple-darwin11- --host=x86_64-apple-darwin11
--target=i686-apple-darwin11 --with-gxx-include-dir=/usr/include/c++/4.2.1
Thread model: posix gcc version 4.2.1 (Based on Apple Inc. build 5658) (LLVM
build 2336.1.00)

[evandrix]

Original tr/unordered_set definition:

...template<class _Value,
       class _Hash = hash<_Value>,
       class _Pred = std::equal_to<_Value>,
       class _Alloc = std::allocator<_Value>,
       bool __cache_hash_code = false>
    class unordered_set

  template<class _Value,
       class _Hash = hash<_Value>,
       class _Pred = std::equal_to<_Value>,
       class _Alloc = std::allocator<_Value>,
       bool __cache_hash_code = false>
    class unordered_multiset...

[evandrix]

I was investigating this further, and believe this discrepancy is caused by using gcc version <=4.2, it works on my machine when i try gcc >= 4.3.

[louisdx]

I've had a look at the TR1 document, too, and that one also specifies the templates precisely way I have them. Moreover, I couldn't find any clause that allows implementations to add further, defaulted template parameters.

That said, I'm not opposed to a small change that adds another version with further template parameters, but I am certainly not going to merge a 1500+ lines change that replaces all my files.

[evandrix]

I tried just added a variant with 5 template parameters instead of 4, but it still triggered the compilation error that I've quoted of a different redefinition of a previous declaration. Not sure how to go with your suggestion, even though I'd be willing to, cause in the original source code for tr1/unordered_set, as I've quoted above, the last template parameter is actually bool ...=false (so there already is a default parameter value for this 5th template parameter, hence is your header file's definition really necessary? or please advise how best should I fix it for myself, other than changing my gcc version to >=4.3?

I'm saying this because I think the following is the right way to overload a function:

   template<class _Value,
       class _Hash = hash<_Value>,
       class _Pred = std::equal_to<_Value>,
       class _Alloc = std::allocator<_Value>,
       bool __cache_hash_code = false>
    class unordered_set

   template<class _Value,
       class _Hash = hash<_Value>,
       class _Pred = std::equal_to<_Value>,
       class _Alloc = std::allocator<_Value>>
    class unordered_set

but having these 2 as it were doesn't seem to compile for me without giving that error.

[louisdx]

Try adding something like this:

  // Pre-declarations of container types so we don't actually have to include the relevant headers if not needed, speeding up compilation time.
template<typename T, typename TComp, typename TAllocator> class set;
template<typename T, typename TComp, typename TAllocator, bool> class set;
template<typename T, typename TComp, typename TAllocator> class multiset;
template<typename T, typename TComp, typename TAllocator, bool> class multiset;

And then:

template<typename T, typename THash, typename TEqual, typename TAllocator, bool BCache>
struct delimiters< ::std::tr1::unordered_set<T, THash, TEqual, TAllocator, BCache>, char> { static const delimiters_values<char> values; };

template<typename T, typename THash, typename TEqual, typename TAllocator, BCache>
const delimiters_values<char> delimiters< ::std::tr1::unordered_set<T, THash, TEqual, TAllocator, BCache>, char>::values = { "{", ", ", "}" };

(And similarly for all the other cases.)