rust/src/libcore/fmt/rt.rs
2014-06-15 23:30:24 -07:00

79 lines
2.4 KiB
Rust

// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
//! This is an internal module used by the ifmt! runtime. These structures are
//! emitted to static arrays to precompile format strings ahead of time.
//!
//! These definitions are similar to their `ct` equivalents, but differ in that
//! these can be statically allocated and are slightly optimized for the runtime
#[doc(hidden)]
pub enum Piece<'a> {
String(&'a str),
Argument(Argument<'a>),
}
#[doc(hidden)]
pub struct Argument<'a> {
pub position: Position,
pub format: FormatSpec,
}
#[doc(hidden)]
pub struct FormatSpec {
pub fill: char,
pub align: Alignment,
pub flags: uint,
pub precision: Count,
pub width: Count,
}
/// Possible alignments that can be requested as part of a formatting directive.
#[deriving(PartialEq)]
pub enum Alignment {
/// Indication that contents should be left-aligned.
AlignLeft,
/// Indication that contents should be right-aligned.
AlignRight,
/// No alignment was requested.
AlignUnknown,
}
#[doc(hidden)]
pub enum Count {
CountIs(uint), CountIsParam(uint), CountIsNextParam, CountImplied,
}
#[doc(hidden)]
pub enum Position {
ArgumentNext, ArgumentIs(uint)
}
/// Flags which can be passed to formatting via a directive.
///
/// These flags are discovered through the `flags` field of the `Formatter`
/// structure. The flag in that structure is a union of these flags into a
/// `uint` where each flag's discriminant is the corresponding bit.
pub enum Flag {
/// A flag which enables number formatting to always print the sign of a
/// number.
FlagSignPlus,
/// Currently not a used flag
FlagSignMinus,
/// Indicates that the "alternate formatting" for a type should be used.
///
/// The meaning of this flag is type-specific.
FlagAlternate,
/// Indicates that padding should be done with a `0` character as well as
/// being aware of the sign to be printed.
FlagSignAwareZeroPad,
}