14d3dbe292
This commit fills in the documentation holes for the FormatWriter trait which were previously accidentally left blank. Additionally, this adds the `write_fmt` method to the trait to allow usage of the `write!` macro with implementors of the `FormatWriter` trait. This is not useful for consumers of the standard library who should generally avoid the `FormatWriter` trait, but it is useful for consumers of the core library who are not using the standard library.
46 lines
1.1 KiB
Rust
46 lines
1.1 KiB
Rust
// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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// no-pretty-expanded
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#![allow(unused_must_use, dead_code)]
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#![feature(macro_rules)]
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use std::io::MemWriter;
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use std::fmt;
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use std::fmt::FormatWriter;
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struct Foo<'a> {
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writer: &'a mut Writer,
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other: &'a str,
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}
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struct Bar;
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impl fmt::FormatWriter for Bar {
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fn write(&mut self, _: &[u8]) -> fmt::Result {
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Ok(())
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}
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}
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fn borrowing_writer_from_struct_and_formatting_struct_field(foo: Foo) {
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write!(foo.writer, "{}", foo.other);
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}
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fn main() {
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let mut w = MemWriter::new();
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write!(&mut w as &mut Writer, "");
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write!(&mut w, ""); // should coerce
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println!("ok");
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let mut s = Bar;
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write!(&mut s, "test");
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}
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