The the last argument of the `ItemDecorator::expand` method has changed to `Box<FnMut>`. Syntax extensions will break.
[breaking-change]
---
This PR removes pretty much all the remaining uses of boxed closures from the libraries. There are still boxed closures under the `test` directory, but I think those should be removed or replaced with unboxed closures at the same time we remove boxed closures from the language.
In a few places I had to do some contortions (see the first commit for an example) to work around issue #19596. I have marked those workarounds with FIXMEs. In the future when `&mut F where F: FnMut` implements the `FnMut` trait, we should be able to remove those workarounds. I've take care to avoid placing the workaround functions in the public API.
Since `let f = || {}` always gets type checked as a boxed closure, I have explictly annotated those closures (with e.g. `|&:| {}`) to force the compiler to type check them as unboxed closures.
Instead of removing the type aliases (like `GetCrateDataCb`), I could have replaced them with newtypes. But this seemed like overcomplicating things for little to no gain.
I think we should be able to remove the boxed closures from the languge after this PR lands. (I'm being optimistic here)
r? @alexcrichton or @aturon
cc @nikomatsakis
is still probably wrong since it fails to incorporate the ambiguity
resolution measures that `select` uses. Also, made more complicated by
the fact that trait object types do not impl their own traits yet.
Patch for #20340. `rustdoc --version` panics because it uses `rustc_driver::version`, which in turn checks the `verbose` flag, which was not defined for rustdoc. In this patch I have added a verbose flag to rustdoc, because I think it should be useful for other things besides --version.
Another possible fix would be to check if a verbose option was defined in `rustc_driver` or add an extra `version` function for rustdoc.
This patch resolves the second problem mentioned in #15877: function calls to integers, e.g. `3.b()`.
It does so, by checking whether the character following the first dot of a FLOAT_LIT is a character or an underscore (these should denote a valid identifier). This does not look like a particularly, but it seems like a lookahead of 1 is needed for this distinction.
Another interesting aspect are ranges that start with a integer constant, but end with a function call, e.g. `1..b()`. Rust treats this as a range from 1 to `b()`, but given that `1.` is a valid FLOAT_LIT, `1..b()` could be a function call to a float as well.
cc @cmr
