r? @pcwalton
A month's worth of parser cleanup here. Much of this is new comments and renaming. A number of these commits also remove unneeded code. Probably the biggest refactor here is splitting "parse_item_or_view_item" into two functions; it turns out that the only overlap between items in foreign modules and items in regular modules was macros, so this refactor should make things substantially easier for future maintenance.
The existing adaptors like `map` in the `iter` module are very flawed because they only work for `BaseIter` implementations. There are many internal iterator implementations in the standard library like the set methods (`difference`, `symmetric_difference`, `intersection`, `union`) and the `range` functions that only share the `for` loop protocol in common.
The internal iterator adaptors should be implemented to work on any implementation of that protocol, rather than just a method called `each` taking `&self`.
This just moves `iter.rs` to `old_iter.rs` and begins work on documenting and implementing a nicer module.
before this change, the parser would parse 14.a() as a method call, but
would parse 14.ø() as the floating-point number 14. followed by a function
call. This is because it was checking is_alpha, rather than ident_start,
and was therefore wrong with respect to unicode.
In principle, it seems like a nice idea to abstract over the two
functions that parse blocks (one with inner attrs allowed, one not).
However, the existing one wound up making things more complex than
just having two separate functions, especially after the obsolete
syntax is (will be) removed.
prec.rs no longer had much to do with precedence; the token->binop
function fits better in token.rs, and the one-liner defining the
precedence of 'as' can go next to the other precedence stuff in
ast_util.rs
r? @brson mkdir_recursive creates a directory as well as any of its
parent directories that don't exist already. Seems like a useful
thing to have in core.
(Or r? anyone who gets to it first.)
As part of the numeric trait reform (see issue #4819), I have added the following traits to `core::num` and implemented them for Rust's primitive numeric types:
~~~rust
pub trait Bitwise: Not<Self>
+ BitAnd<Self,Self>
+ BitOr<Self,Self>
+ BitXor<Self,Self>
+ Shl<Self,Self>
+ Shr<Self,Self> {}
pub trait BitCount {
fn population_count(&self) -> Self;
fn leading_zeros(&self) -> Self;
fn trailing_zeros(&self) -> Self;
}
pub trait Bounded {
fn min_value() -> Self;
fn max_value() -> Self;
}
pub trait Primitive: Num
+ NumCast
+ Bounded
+ Neg<Self>
+ Add<Self,Self>
+ Sub<Self,Self>
+ Mul<Self,Self>
+ Quot<Self,Self>
+ Rem<Self,Self> {
fn bits() -> uint;
fn bytes() -> uint;
}
pub trait Int: Integer
+ Primitive
+ Bitwise
+ BitCount {}
pub trait Float: Real
+ Signed
+ Primitive {
fn NaN() -> Self;
fn infinity() -> Self;
fn neg_infinity() -> Self;
fn neg_zero() -> Self;
fn is_NaN(&self) -> bool;
fn is_infinite(&self) -> bool;
fn is_finite(&self) -> bool;
fn mantissa_digits() -> uint;
fn digits() -> uint;
fn epsilon() -> Self;
fn min_exp() -> int;
fn max_exp() -> int;
fn min_10_exp() -> int;
fn max_10_exp() -> int;
fn mul_add(&self, a: Self, b: Self) -> Self;
fn next_after(&self, other: Self) -> Self;
}
~~~
Note: I'm not sure my implementation for `BitCount::trailing_zeros` and `BitCount::leading_zeros` is correct for uints. I also need some assistance creating appropriate unit tests for them.
More work needs to be done in implementing specialized primitive floating-point and integer methods, but I'm beginning to reach the limits of my knowledge. Please leave your suggestions/critiques/ideas on #4819 if you have them – I'd very much appreciate hearing them.
I have also added an `Orderable` trait:
~~~rust
pub trait Orderable: Ord {
fn min(&self, other: &Self) -> Self;
fn max(&self, other: &Self) -> Self;
fn clamp(&self, mn: &Self, mx: &Self) -> Self;
}
~~~
This is a temporary trait until we have default methods. We don't want to encumber all implementors of Ord by requiring them to implement these functions, but at the same time we want to be able to take advantage of the speed of the specific numeric functions (like the `fmin` and `fmax` intrinsics).
r? @brson
Unwinding through macros now happens as a call to the trait function `FailWithCause::fail_with()`, which consumes self, allowing to use a more generic failure object in the future.
