It's unclear to me why these currently aren't allowed, and my best guess is that
a long time ago we didn't strip the ast of cfg nodes before syntax expansion.
Now that this is done, I'm not certain that we should continue to prohibit this
functionality.
This is a step in the right direction towards #5605, because now we can add an
empty `std::macros` module to the documentation with a bunch of empty macros
explaining how they're supposed to be used.
It's unclear to me why these currently aren't allowed, and my best guess is that
a long time ago we didn't strip the ast of cfg nodes before syntax expansion.
Now that this is done, I'm not certain that we should continue to prohibit this
functionality.
This is a step in the right direction towards #5605, because now we can add an
empty `std::macros` module to the documentation with a bunch of empty macros
explaining how they're supposed to be used.
r? anybody It's more helpful to list the span of each open delimiter seen so far
than to print out an error with the span of the last position in the file.
Closes#2354
For the benefit of the pretty printer we want to keep track of how
string literals in the ast were originally represented in the source
code.
This commit changes parser functions so they don't extract strings from
the token stream without at least also returning what style of string
literal it was. This is stored in the resulting ast node for string
literals, obviously, for the package id in `extern mod = r"package id"`
view items, for the inline asm in `asm!()` invocations.
For `asm!()`'s other arguments or for `extern "Rust" fn()` items, I just
the style of string, because it seemed disproportionally cumbersome to
thread that information through the string processing that happens with
those string literals, given the limited advantage raw string literals
would provide in these positions.
The other syntax extensions don't seem to store passed string literals
in the ast, so they also discard the style of strings they parse.
It's more helpful to list the span of each open delimiter seen so far
than to print out an error with the span of the last position in the file.
Closes#2354
Raw string literals are lexed into regular string literals. This is okay
for them to "work" and be usable/testable, but the pretty-printer does
not know about them yet and will just emit regular string literals.
This commit fixes all of the fallout of the previous commit which is an attempt
to refine privacy. There were a few unfortunate leaks which now must be plugged,
and the most horrible one is the current `shouldnt_be_public` module now inside
`std::rt`. I think that this either needs a slight reorganization of the
runtime, or otherwise it needs to just wait for the external users of these
modules to get replaced with their `rt` implementations.
Other fixes involve making things pub which should be pub, and otherwise
updating error messages that now reference privacy instead of referencing an
"unresolved name" (yay!).
This commit is the culmination of my recent effort to refine Rust's notion of
privacy and visibility among crates. The major goals of this commit were to
remove privacy checking from resolve for the sake of sane error messages, and to
attempt a much more rigid and well-tested implementation of visibility
throughout rust. The implemented rules for name visibility are:
1. Everything pub from the root namespace is visible to anyone
2. You may access any private item of your ancestors.
"Accessing a private item" depends on what the item is, so for a function this
means that you can call it, but for a module it means that you can look inside
of it. Once you look inside a private module, any accessed item must be "pub
from the root" where the new root is the private module that you looked into.
These rules required some more analysis results to get propagated from trans to
privacy in the form of a few hash tables.
I added a new test in which my goal was to showcase all of the privacy nuances
of the language, and I hope to place any new bugs into this file to prevent
regressions.
Overall, I was unable to completely remove the notion of privacy from resolve.
One use of privacy is for dealing with glob imports. Essentially a glob import
can only import *public* items from the destination, and because this must be
done at namespace resolution time, resolve must maintain the notion of "what
items are public in a module". There are some sad approximations of privacy, but
I unfortunately can't see clear methods to extract them outside.
The other use case of privacy in resolve now is one that must stick around
regardless of glob imports. When dealing with privacy, checking a private path
needs to know "what the last private thing was" when looking at a path. Resolve
is the only compiler pass which knows the answer to this question, so it
maintains the answer on a per-path resolution basis (works similarly to the
def_map generated).
Closes#8215
A few features are now hidden behind various #[feature(...)] directives. These
include struct-like enum variants, glob imports, and macro_rules! invocations.
Closes#9304Closes#9305Closes#9306Closes#9331
This PR solves one of the pain points with c-style enums. Simplifies writing a fn to convert from an int/uint to an enum. It does this through a `#[deriving(FromPrimitive)]` syntax extension.
Before this is committed though, we need to discuss if `ToPrimitive`/`FromPrimitive` has the right design (cc #4819). I've changed all the `.to_int()` and `from_int()` style functions to return `Option<int>` so we can handle partial functions. For this PR though only enums and `extra::num::bigint::*` take advantage of returning None for unrepresentable values. In the long run it'd be better if `i64.to_i8()` returned `None` if the value was too large, but I'll save this for a future PR.
Closes#3868.
Replaces existing tests for removed obsolete-syntax errors with tests
for the resulting regular errors, adds a test for each of the removed
parser errors to make sure that obsolete forms don't start working
again, removes some obsolete/superfluous tests that were now failing.
Deletes some amount of dead code in the parser, also includes some small
changes to parser error messages to accomodate new tests.
This purges about 500 lines of visitor cruft from lint passes. All lints are
handled in a much more sane way at this point. The other huge bonus of this
commit is that there are no more @-boxes in the lint passes, fixing the 500MB
memory regression seen when the lint passes were refactored.
Closes#8589
One downside with this current implementation is that since BigInt's
default is now 64 bit, we can convert larger BigInt's to a primitive,
however the current implementation on 32 bit architectures does not
take advantage of this fact.
That is, only a single expression or item gets parsed, so if there are
any extra tokens (e.g. the start of another item/expression) the user
should be told, rather than silently dropping them.
An example:
macro_rules! foo {
() => {
println("hi");
println("bye);
}
}
would expand to just `println("hi")`, which is almost certainly not
what the programmer wanted.
Fixes#8012.
That is, only a single expression or item gets parsed, so if there are
any extra tokens (e.g. the start of another item/expression) the user
should be told, rather than silently dropping them.
An example:
macro_rules! foo {
() => {
println("hi");
println("bye);
}
}
would expand to just `println("hi")`, which is almost certainly not
what the programmer wanted.
Fixes#8012.
It is simply defined as `f64` across every platform right now.
A use case hasn't been presented for a `float` type defined as the
highest precision floating point type implemented in hardware on the
platform. Performance-wise, using the smallest precision correct for the
use case greatly saves on cache space and allows for fitting more
numbers into SSE/AVX registers.
If there was a use case, this could be implemented as simply a type
alias or a struct thanks to `#[cfg(...)]`.
Closes#6592
The mailing list thread, for reference:
https://mail.mozilla.org/pipermail/rust-dev/2013-July/004632.html
It is simply defined as `f64` across every platform right now.
A use case hasn't been presented for a `float` type defined as the
highest precision floating point type implemented in hardware on the
platform. Performance-wise, using the smallest precision correct for the
use case greatly saves on cache space and allows for fitting more
numbers into SSE/AVX registers.
If there was a use case, this could be implemented as simply a type
alias or a struct thanks to `#[cfg(...)]`.
Closes#6592
The mailing list thread, for reference:
https://mail.mozilla.org/pipermail/rust-dev/2013-July/004632.html
We're not outright removing fmt! just yet, but this prevents it from leaking
into the compiler further (it's still turned on by default for all other code).
As mentioned in #9456, the format! syntax extension would previously consider an
empty format as a 'Unknown' format which could then also get coerced into a
different style of format on another argument.
This is unusual behavior because `{}` is a very common format and if you have
`{0} {0:?}` you wouldn't expect them both to be coereced to the `Poly`
formatter. This commit removes this coercion, but still retains the requirement
that each argument has exactly one format specified for it (an empty format now
counts as well).
Perhaps at a later date we can add support for multiple formats of one argument,
but this puts us in at least a backwards-compatible situation if we decide to do
that.
As mentioned in #9456, the format! syntax extension would previously consider an
empty format as a 'Unknown' format which could then also get coerced into a
different style of format on another argument.
This is unusual behavior because `{}` is a very common format and if you have
`{0} {0:?}` you wouldn't expect them both to be coereced to the `Poly`
formatter. This commit removes this coercion, but still retains the requirement
that each argument has exactly one format specified for it (an empty format now
counts as well).
Perhaps at a later date we can add support for multiple formats of one argument,
but this puts us in at least a backwards-compatible situation if we decide to do
that.
This lifts various restrictions on the runtime, for example the character limit
when logging a message. Right now the old debug!-style macros still involve
allocating (because they use fmt! syntax), but the new debug2! macros don't
involve allocating at all (unless the formatter for a type requires allocation.
