Prelexer alternatives fails with 7 arguments

[xzyfer]

During the development of #744 I ran into issue with this

sequence< interpolant, alternatives< identifier, 
                          percentage, 
                          dimension, 
                          hex, 
                          number, 
                          string_constant, 
                          exactly<'%'> > >(src);

it works however if any argument is removed.

[QuLogic]

What's the error? It appears that alternatives is defined for up to 8 arguments. But the 7 and 8 versions include rslt = src which the lesser argument versions don't. Maybe that's all that could fix it?

[xzyfer]

No error, it would just fail to match. I took a (really?) quick look for difference between the 6 and 7 arg versions.

You're probably right. I'll give it a shot.

[akhleung]

I guess that's what I get for copying and pasting code :-/. If you're already committed to using C++11, then maybe the sequence and alternatives prelexers could be rewritten to use variadic templates.

[xzyfer]

We're committed to unordered_map at least for the foreseeable future so it's probably worth going all in on cpp11

[mgreter]

I would speak against using the full feature set of cpp11, it already intoduced some headaches for the node-sass people since they provide prebuilt binaries. Some people still seem to be on systems which only provide gcc 4.4. ...

[xzyfer]

Cool. It'd be good to have guidelines on what will cause pain for people in gcc <= 4.4.

[mgreter]

Pretty funny that this emerges the day I tried to compile it with gcc 4.4.4 => mgreter@14e1d7a
We would be able to replace pretty much anything with std C C++ beside uniform_real_distribution and unordered_map (with the latter beeing available for gcc 4.4.4).

[xzyfer]

Needless to say replacing things with C does not thrill me.

[mgreter]

Sorry, should be std c++ 99 😉 But I know, C++11 has some nice syntax sugar. Specially looping over containers, which is what we mostly use beside the other two features, which are much harder to replace (I guess).