r? @graydon
This removes `log` from the language. Because we can't quite implement it as a syntax extension (probably need globals at the least) it simply renames the keyword to `__log` and hides it behind macros.
After this the only way to log is with `debug!`, `info!`, etc. I figure that if there is demand for `log!` we can add it back later.
I am not sure that we ever agreed on this course of action, though I *think* there is consensus that `log` shouldn't be a statement.
This is the first in a series of patches I'm working on to clean up the code related to `deriving`. This patch allows
```
#[deriving_eq]
#[deriving_iter_bytes]
#[deriving_clone]
struct Foo { bar: uint }
```
to be replaced with:
```
#[deriving(Eq, IterBytes, Clone)]
struct Foo { bar: uint }
```
It leaves the old attributes alone for the time being.
Eventually I'd like to incorporate the new closest-match-suggestion infrastructure for mistyped trait names, and also pass the sub-attributes to the deriving code, so that the following will be possible:
```
#[deriving(TotalOrd(qux, bar))]
struct Foo { bar: uint, baz: char, qux: int }
```
This says to derive an `impl` in which the objects' `qux` fields are compared first, followed by `bar`, while `baz` is ignored in the comparison. If no fields are specified explicitly, all fields will be compared in the order they're defined in the `struct`. This might also be useful for `Eq`. Coming soon.
r?
`log` can polymorphically log anything, but debug!, etc. requires a format string. With this patch you can equivalently write `debug!(foo)` or `debug!("%?", foo)`.
I'm doing this because I was trying to remove `log` (replacing it with nothing, at least temporarily), but there are a number of logging statements that just want to print an arbitrary value and don't care about the format string.
I'm not entirely convinced this is a good change, since it overloads the implementation of these macros and makes their usage slightly more nuanced.
The one thing `log` can still do is polymorphically log anything,
but debug!, etc. require a format string. With this patch
you can equivalently write `debug!(foo)` or `debug!("%?", foo)`
After the removal of the "restricted keyword" feature in 0c82c00dc4f49aeb9b57c92c9a40ae35d8a1ee29 , there's no longer any difference between parse_ident() and parse_value_ident(), and therefore no difference between parse parse_path_without_tps() and parse_value_path(). I've collapsed all of these, removing the redundant functions and eliminating the need for two higher-order arguments.
Macro invocations with path separators (e.g. foo::bar!()) now produce a sensible error message, rather than an assertion failure. Also added compile-fail test case.
Fixes#5218 ?
I've found that unused imports can often start cluttering a project after a long time, and it's very useful to keep them under control. I don't like how Go forces a compiler error by default and it can't be changed, but I certainly want to know about them so I think that a warn is a good default.
Now that the `unused_imports` lint option is a bit smarter, I think it's possible to change the default level to warn. This commit also removes all unused imports throughout the compiler and libraries (500+).
The only odd things that I ran into were that some `use` statements had to have `#[cfg(notest)]` or `#[cfg(test)]` based on where they were. The ones with `notest` were mostly in core for modules like `cmp` whereas `cfg(test)` was for tests that weren't part of a normal `mod test` module.
My merges for #5143 missed a couple other copies. This patch corrects this, and gets stage0 to compile libsyntax with `#[deny(vecs_implicitly_copyable)]`. stage1 still fails though.
