std: Extract format string parsing out of libstd

This code does not belong in libstd, and rather belongs in a dedicated crate. In
the future, the syntax::ext::format module should move to the fmt_macros crate
(hence the name of the crate), but for now the fmt_macros crate will only
contain the format string parser.

The entire fmt_macros crate is marked #[experimental] because it is not meant
for general consumption, only the format!() interface is officially supported,
not the internals.

This is a breaking change for anyone using the internals of std::fmt::parse.
Some of the flags have moved to std::fmt::rt, while the actual parsing support
has all moved to the fmt_macros library.

[breaking-change]

1 files changed, 35 insertions, 3 deletions

diff --git a/src/libstd/fmt/rt.rs b/src/libstd/fmt/rt.rs
index 01c2c06c3fb..33e86a4485b 100644
--- a/src/libstd/fmt/rt.rs
+++ b/src/libstd/fmt/rt.rs
@@ -17,9 +17,17 @@
 #![allow(missing_doc)]
 #![doc(hidden)]
 
-use fmt::parse;
 use option::Option;
 
+#[cfg(stage0)]
+pub use fmt::parse::{Alignment, AlignLeft, AlignRight, AlignUnknown};
+#[cfg(stage0)]
+pub use fmt::parse::{PluralKeyword, Zero, One, Two, Few, Many};
+#[cfg(stage0)]
+pub use fmt::parse::{Flag, FlagSignPlus, FlagSignMinus, FlagSignAwareZeroPad};
+#[cfg(stage0)]
+pub use fmt::parse::{FlagAlternate};
+
 pub enum Piece<'a> {
     String(&'a str),
     // FIXME(#8259): this shouldn't require the unit-value here
@@ -35,12 +43,20 @@ pub struct Argument<'a> {
 
 pub struct FormatSpec {
     pub fill: char,
-    pub align: parse::Alignment,
+    pub align: Alignment,
     pub flags: uint,
     pub precision: Count,
     pub width: Count,
 }
 
+#[cfg(not(stage0))]
+#[deriving(Eq)]
+pub enum Alignment {
+    AlignLeft,
+    AlignRight,
+    AlignUnknown,
+}
+
 pub enum Count {
     CountIs(uint), CountIsParam(uint), CountIsNextParam, CountImplied,
 }
@@ -49,16 +65,32 @@ pub enum Position {
     ArgumentNext, ArgumentIs(uint)
 }
 
+#[cfg(not(stage0))]
+pub enum Flag {
+    FlagSignPlus,
+    FlagSignMinus,
+    FlagAlternate,
+    FlagSignAwareZeroPad,
+}
+
 pub enum Method<'a> {
     Plural(Option<uint>, &'a [PluralArm<'a>], &'a [Piece<'a>]),
     Select(&'a [SelectArm<'a>], &'a [Piece<'a>]),
 }
 
 pub enum PluralSelector {
-    Keyword(parse::PluralKeyword),
+    Keyword(PluralKeyword),
     Literal(uint),
 }
 
+pub enum PluralKeyword {
+    Zero,
+    One,
+    Two,
+    Few,
+    Many,
+}
+
 pub struct PluralArm<'a> {
     pub selector: PluralSelector,
     pub result: &'a [Piece<'a>],