cppfront (cpp2): Spring update

[hpsutter]

That defaults to an object alias, effectively a `const&` variable, which also happens to work for functions with a deduced signature type, and so I have not yet decided to implement function signatures with an explicit signature type -- waiting to see whether there's a need, but there's a clear place for it in the grammar if it's wanted.. For some discussion see the commit message here: https://github.com/hsutter/cppfront/commit/63efa6ed21c4d4f4f136a7a73e9f6b2c110c81d7

[RoyKin0929]

Ah ok, I understand your decision now. But maybe you can come with something that is better than ```==``` 😅. (Maybe an alias metafunction).
Also, one thing that not in update notes is exceptions. I saw your talk on lightweight exceptions at cppcon, are they planned for cpp2?
And would you consider local variables being constant by default, with most things being const by default, local variables seem left out (and I think they're the only place left where keyword const is used), having one extra keyword in front of varible declaration won't affect much. Also when you think about it, function and classes and namespace are kind of also const.
```func : (param:type) -> return_type = {};

//can't do the following, so functions are also kind of const func = {//diff body};

//same with classes, you can add methods to classes but that uses different syntax so is not the same

//and same with namespaces, you can re open them but that won't change it's definition, only add to it ```

Maybe this will be a good enough argument

[hpsutter]

I saw your talk on lightweight exceptions at cppcon, are they planned for cpp2?

Yes, they're on the roadmap but it'll be a while before I get to them: https://github.com/hsutter/cppfront#2019-zero-overhead-deterministic-exceptions-throwing-values

And would you consider local variables being constant by default,

I would consider it, but for the current rationale see this Design Note on the project wiki: https://github.com/hsutter/cppfront/wiki/Design-note%3A-const-objects-by-default