Make std::fmt a simple re-export from collections

2 files changed, 1 insertions, 415 deletions

diff --git a/src/libstd/fmt.rs b/src/libstd/fmt.rs
deleted file mode 100644
index 82823f0cb28..00000000000
--- a/src/libstd/fmt.rs
+++ /dev/null
@@ -1,414 +0,0 @@
-// Copyright 2013-2014 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.
-//
-// ignore-lexer-test FIXME #15679
-
-//! Utilities for formatting and printing strings
-//!
-//! This module contains the runtime support for the `format!` syntax extension.
-//! This macro is implemented in the compiler to emit calls to this module in
-//! order to format arguments at runtime into strings and streams.
-//!
-//! ## Usage
-//!
-//! The `format!` macro is intended to be familiar to those coming from C's
-//! printf/fprintf functions or Python's `str.format` function. In its current
-//! revision, the `format!` macro returns a `String` type which is the result of
-//! the formatting. In the future it will also be able to pass in a stream to
-//! format arguments directly while performing minimal allocations.
-//!
-//! Some examples of the `format!` extension are:
-//!
-//! ```
-//! format!("Hello");                  // => "Hello"
-//! format!("Hello, {}!", "world");    // => "Hello, world!"
-//! format!("The number is {}", 1);   // => "The number is 1"
-//! format!("{:?}", (3, 4));         // => "(3, 4)"
-//! format!("{value}", value=4);      // => "4"
-//! format!("{} {}", 1, 2u);          // => "1 2"
-//! ```
-//!
-//! From these, you can see that the first argument is a format string. It is
-//! required by the compiler for this to be a string literal; it cannot be a
-//! variable passed in (in order to perform validity checking). The compiler
-//! will then parse the format string and determine if the list of arguments
-//! provided is suitable to pass to this format string.
-//!
-//! ### Positional parameters
-//!
-//! Each formatting argument is allowed to specify which value argument it's
-//! referencing, and if omitted it is assumed to be "the next argument". For
-//! example, the format string `{} {} {}` would take three parameters, and they
-//! would be formatted in the same order as they're given. The format string
-//! `{2} {1} {0}`, however, would format arguments in reverse order.
-//!
-//! Things can get a little tricky once you start intermingling the two types of
-//! positional specifiers. The "next argument" specifier can be thought of as an
-//! iterator over the argument. Each time a "next argument" specifier is seen,
-//! the iterator advances. This leads to behavior like this:
-//!
-//! ```rust
-//! format!("{1} {} {0} {}", 1, 2); // => "2 1 1 2"
-//! ```
-//!
-//! The internal iterator over the argument has not been advanced by the time
-//! the first `{}` is seen, so it prints the first argument. Then upon reaching
-//! the second `{}`, the iterator has advanced forward to the second argument.
-//! Essentially, parameters which explicitly name their argument do not affect
-//! parameters which do not name an argument in terms of positional specifiers.
-//!
-//! A format string is required to use all of its arguments, otherwise it is a
-//! compile-time error. You may refer to the same argument more than once in the
-//! format string, although it must always be referred to with the same type.
-//!
-//! ### Named parameters
-//!
-//! Rust itself does not have a Python-like equivalent of named parameters to a
-//! function, but the `format!` macro is a syntax extension which allows it to
-//! leverage named parameters. Named parameters are listed at the end of the
-//! argument list and have the syntax:
-//!
-//! ```text
-//! identifier '=' expression
-//! ```
-//!
-//! For example, the following `format!` expressions all use named argument:
-//!
-//! ```
-//! format!("{argument}", argument = "test");   // => "test"
-//! format!("{name} {}", 1, name = 2);        // => "2 1"
-//! format!("{a} {c} {b}", a="a", b='b', c=3);  // => "a 3 b"
-//! ```
-//!
-//! It is illegal to put positional parameters (those without names) after
-//! arguments which have names. Like with positional parameters, it is illegal
-//! to provide named parameters that are unused by the format string.
-//!
-//! ### Argument types
-//!
-//! Each argument's type is dictated by the format string. It is a requirement
-//! that every argument is only ever referred to by one type. For example, this
-//! is an invalid format string:
-//!
-//! ```text
-//! {0:x} {0:o}
-//! ```
-//!
-//! This is invalid because the first argument is both referred to as a
-//! hexadecimal as well as an
-//! octal.
-//!
-//! There are various parameters which do require a particular type, however.
-//! Namely if the syntax `{:.*}` is used, then the number of characters to print
-//! precedes the actual object being formatted, and the number of characters
-//! must have the type `uint`. Although a `uint` can be printed with `{}`, it is
-//! illegal to reference an argument as such. For example this is another
-//! invalid format string:
-//!
-//! ```text
-//! {:.*} {0}
-//! ```
-//!
-//! ### Formatting traits
-//!
-//! When requesting that an argument be formatted with a particular type, you
-//! are actually requesting that an argument ascribes to a particular trait.
-//! This allows multiple actual types to be formatted via `{:x}` (like `i8` as
-//! well as `int`).  The current mapping of types to traits is:
-//!
-//! * *nothing* ⇒ `Display`
-//! * `?` ⇒ `Debug`
-//! * `o` ⇒ `Octal`
-//! * `x` ⇒ `LowerHex`
-//! * `X` ⇒ `UpperHex`
-//! * `p` ⇒ `Pointer`
-//! * `b` ⇒ `Binary`
-//! * `e` ⇒ `LowerExp`
-//! * `E` ⇒ `UpperExp`
-//!
-//! What this means is that any type of argument which implements the
-//! `std::fmt::Binary` trait can then be formatted with `{:b}`. Implementations
-//! are provided for these traits for a number of primitive types by the
-//! standard library as well. If no format is specified (as in `{}` or `{:6}`),
-//! then the format trait used is the `Display` trait.
-//!
-//! When implementing a format trait for your own type, you will have to
-//! implement a method of the signature:
-//!
-//! ```rust
-//! # use std::fmt;
-//! # struct Foo; // our custom type
-//! # impl fmt::Display for Foo {
-//! fn fmt(&self, f: &mut std::fmt::Formatter) -> fmt::Result {
-//! # write!(f, "testing, testing")
-//! # } }
-//! ```
-//!
-//! Your type will be passed as `self` by-reference, and then the function
-//! should emit output into the `f.buf` stream. It is up to each format trait
-//! implementation to correctly adhere to the requested formatting parameters.
-//! The values of these parameters will be listed in the fields of the
-//! `Formatter` struct. In order to help with this, the `Formatter` struct also
-//! provides some helper methods.
-//!
-//! Additionally, the return value of this function is `fmt::Result` which is a
-//! typedef to `Result<(), IoError>` (also known as `IoResult<()>`). Formatting
-//! implementations should ensure that they return errors from `write!`
-//! correctly (propagating errors upward).
-//!
-//! An example of implementing the formatting traits would look
-//! like:
-//!
-//! ```rust
-//! use std::fmt;
-//! use std::f64;
-//! use std::num::Float;
-//!
-//! #[derive(Debug)]
-//! struct Vector2D {
-//!     x: int,
-//!     y: int,
-//! }
-//!
-//! impl fmt::Display for Vector2D {
-//!     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-//!         // The `f` value implements the `Writer` trait, which is what the
-//!         // write! macro is expecting. Note that this formatting ignores the
-//!         // various flags provided to format strings.
-//!         write!(f, "({}, {})", self.x, self.y)
-//!     }
-//! }
-//!
-//! // Different traits allow different forms of output of a type. The meaning
-//! // of this format is to print the magnitude of a vector.
-//! impl fmt::Binary for Vector2D {
-//!     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-//!         let magnitude = (self.x * self.x + self.y * self.y) as f64;
-//!         let magnitude = magnitude.sqrt();
-//!
-//!         // Respect the formatting flags by using the helper method
-//!         // `pad_integral` on the Formatter object. See the method documentation
-//!         // for details, and the function `pad` can be used to pad strings.
-//!         let decimals = f.precision().unwrap_or(3);
-//!         let string = f64::to_str_exact(magnitude, decimals);
-//!         f.pad_integral(true, "", string.as_slice())
-//!     }
-//! }
-//!
-//! fn main() {
-//!     let myvector = Vector2D { x: 3, y: 4 };
-//!
-//!     println!("{}", myvector);       // => "(3, 4)"
-//!     println!("{:?}", myvector);     // => "Vector2D {x: 3, y:4}"
-//!     println!("{:10.3b}", myvector); // => "     5.000"
-//! }
-//! ```
-//!
-//! #### fmt::Display vs fmt::Debug
-//!
-//! These two formatting traits have distinct purposes:
-//!
-//! - `fmt::Display` implementations assert that the type can be faithfully
-//!   represented as a UTF-8 string at all times. It is **not** expected that
-//!   all types implement the `Display` trait.
-//! - `fmt::Debug` implementations should be implemented for **all** public types.
-//!   Output will typically represent the internal state as faithfully as possible.
-//!   The purpose of the `Debug` trait is to facilitate debugging Rust code. In
-//!   most cases, using `#[derive(Debug)]` is sufficient and recommended.
-//!
-//! Some examples of the output from both traits:
-//!
-//! ```
-//! assert_eq!(format!("{} {:?}", 3i32, 4i32), "3 4");
-//! assert_eq!(format!("{} {:?}", 'a', 'b'), "a 'b'");
-//! assert_eq!(format!("{} {:?}", "foo\n", "bar\n"), "foo\n \"bar\\n\"");
-//! ```
-//!
-//! ### Related macros
-//!
-//! There are a number of related macros in the `format!` family. The ones that
-//! are currently implemented are:
-//!
-//! ```ignore
-//! format!      // described above
-//! write!       // first argument is a &mut old_io::Writer, the destination
-//! writeln!     // same as write but appends a newline
-//! print!       // the format string is printed to the standard output
-//! println!     // same as print but appends a newline
-//! format_args! // described below.
-//! ```
-//!
-//! #### `write!`
-//!
-//! This and `writeln` are two macros which are used to emit the format string
-//! to a specified stream. This is used to prevent intermediate allocations of
-//! format strings and instead directly write the output. Under the hood, this
-//! function is actually invoking the `write` function defined in this module.
-//! Example usage is:
-//!
-//! ```rust
-//! # #![allow(unused_must_use)]
-//! let mut w = Vec::new();
-//! write!(&mut w, "Hello {}!", "world");
-//! ```
-//!
-//! #### `print!`
-//!
-//! This and `println` emit their output to stdout. Similarly to the `write!`
-//! macro, the goal of these macros is to avoid intermediate allocations when
-//! printing output. Example usage is:
-//!
-//! ```rust
-//! print!("Hello {}!", "world");
-//! println!("I have a newline {}", "character at the end");
-//! ```
-//!
-//! #### `format_args!`
-//! This is a curious macro which is used to safely pass around
-//! an opaque object describing the format string. This object
-//! does not require any heap allocations to create, and it only
-//! references information on the stack. Under the hood, all of
-//! the related macros are implemented in terms of this. First
-//! off, some example usage is:
-//!
-//! ```
-//! use std::fmt;
-//! use std::old_io;
-//!
-//! fmt::format(format_args!("this returns {}", "String"));
-//!
-//! let mut some_writer = old_io::stdout();
-//! write!(&mut some_writer, "{}", format_args!("print with a {}", "macro"));
-//!
-//! fn my_fmt_fn(args: fmt::Arguments) {
-//!     write!(&mut old_io::stdout(), "{}", args);
-//! }
-//! my_fmt_fn(format_args!("or a {} too", "function"));
-//! ```
-//!
-//! The result of the `format_args!` macro is a value of type `fmt::Arguments`.
-//! This structure can then be passed to the `write` and `format` functions
-//! inside this module in order to process the format string.
-//! The goal of this macro is to even further prevent intermediate allocations
-//! when dealing formatting strings.
-//!
-//! For example, a logging library could use the standard formatting syntax, but
-//! it would internally pass around this structure until it has been determined
-//! where output should go to.
-//!
-//! ## Syntax
-//!
-//! The syntax for the formatting language used is drawn from other languages,
-//! so it should not be too alien. Arguments are formatted with python-like
-//! syntax, meaning that arguments are surrounded by `{}` instead of the C-like
-//! `%`. The actual grammar for the formatting syntax is:
-//!
-//! ```text
-//! format_string := <text> [ format <text> ] *
-//! format := '{' [ argument ] [ ':' format_spec ] '}'
-//! argument := integer | identifier
-//!
-//! format_spec := [[fill]align][sign]['#'][0][width]['.' precision][type]
-//! fill := character
-//! align := '<' | '^' | '>'
-//! sign := '+' | '-'
-//! width := count
-//! precision := count | '*'
-//! type := identifier | ''
-//! count := parameter | integer
-//! parameter := integer '$'
-//! ```
-//!
-//! ## Formatting Parameters
-//!
-//! Each argument being formatted can be transformed by a number of formatting
-//! parameters (corresponding to `format_spec` in the syntax above). These
-//! parameters affect the string representation of what's being formatted. This
-//! syntax draws heavily from Python's, so it may seem a bit familiar.
-//!
-//! ### Fill/Alignment
-//!
-//! The fill character is provided normally in conjunction with the `width`
-//! parameter. This indicates that if the value being formatted is smaller than
-//! `width` some extra characters will be printed around it. The extra
-//! characters are specified by `fill`, and the alignment can be one of two
-//! options:
-//!
-//! * `<` - the argument is left-aligned in `width` columns
-//! * `^` - the argument is center-aligned in `width` columns
-//! * `>` - the argument is right-aligned in `width` columns
-//!
-//! ### Sign/#/0
-//!
-//! These can all be interpreted as flags for a particular formatter.
-//!
-//! * '+' - This is intended for numeric types and indicates that the sign
-//!         should always be printed. Positive signs are never printed by
-//!         default, and the negative sign is only printed by default for the
-//!         `Signed` trait. This flag indicates that the correct sign (+ or -)
-//!         should always be printed.
-//! * '-' - Currently not used
-//! * '#' - This flag is indicates that the "alternate" form of printing should
-//!         be used. By default, this only applies to the integer formatting
-//!         traits and performs like:
-//!     * `x` - precedes the argument with a "0x"
-//!     * `X` - precedes the argument with a "0x"
-//!     * `t` - precedes the argument with a "0b"
-//!     * `o` - precedes the argument with a "0o"
-//! * '0' - This is used to indicate for integer formats that the padding should
-//!         both be done with a `0` character as well as be sign-aware. A format
-//!         like `{:08d}` would yield `00000001` for the integer `1`, while the
-//!         same format would yield `-0000001` for the integer `-1`. Notice that
-//!         the negative version has one fewer zero than the positive version.
-//!
-//! ### Width
-//!
-//! This is a parameter for the "minimum width" that the format should take up.
-//! If the value's string does not fill up this many characters, then the
-//! padding specified by fill/alignment will be used to take up the required
-//! space.
-//!
-//! The default fill/alignment for non-numerics is a space and left-aligned. The
-//! defaults for numeric formatters is also a space but with right-alignment. If
-//! the '0' flag is specified for numerics, then the implicit fill character is
-//! '0'.
-//!
-//! The value for the width can also be provided as a `uint` in the list of
-//! parameters by using the `2$` syntax indicating that the second argument is a
-//! `uint` specifying the width.
-//!
-//! ### Precision
-//!
-//! For non-numeric types, this can be considered a "maximum width". If the
-//! resulting string is longer than this width, then it is truncated down to
-//! this many characters and only those are emitted.
-//!
-//! For integral types, this has no meaning currently.
-//!
-//! For floating-point types, this indicates how many digits after the decimal
-//! point should be printed.
-//!
-//! ## Escaping
-//!
-//! The literal characters `{` and `}` may be included in a string by preceding
-//! them with the same character. For example, the `{` character is escaped with
-//! `{{` and the `}` character is escaped with `}}`.
-
-#![unstable(feature = "std_misc")]
-
-pub use core::fmt::{Formatter, Result, Writer, rt};
-pub use core::fmt::{Show, String, Octal, Binary};
-pub use core::fmt::{Display, Debug};
-pub use core::fmt::{LowerHex, UpperHex, Pointer};
-pub use core::fmt::{LowerExp, UpperExp};
-pub use core::fmt::Error;
-pub use core::fmt::{ArgumentV1, Arguments, write, radix, Radix, RadixFmt};
-
-pub use core_collections::fmt::format;
diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index 2a523356f62..9a9a554ec98 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -181,6 +181,7 @@ pub use core::error;
 #[cfg(not(test))] pub use alloc::boxed;
 pub use alloc::rc;
 
+pub use core_collections::fmt;
 pub use core_collections::slice;
 pub use core_collections::str;
 pub use core_collections::string;
@@ -246,7 +247,6 @@ pub mod thread_local;
 
 pub mod dynamic_lib;
 pub mod ffi;
-pub mod fmt;
 pub mod old_io;
 pub mod io;
 pub mod os;