41 lines
2.0 KiB
Rust
41 lines
2.0 KiB
Rust
//
|
|
// Copyright (c) 2016 KAMADA Ken'ichi.
|
|
// All rights reserved.
|
|
//
|
|
// Redistribution and use in source and binary forms, with or without
|
|
// modification, are permitted provided that the following conditions
|
|
// are met:
|
|
// 1. Redistributions of source code must retain the above copyright
|
|
// notice, this list of conditions and the following disclaimer.
|
|
// 2. Redistributions in binary form must reproduce the above copyright
|
|
// notice, this list of conditions and the following disclaimer in the
|
|
// documentation and/or other materials provided with the distribution.
|
|
//
|
|
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
// ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
// SUCH DAMAGE.
|
|
//
|
|
|
|
// This is not an enum to keep safety and API stability, while
|
|
// supporting unknown tag values. This comment is based on the
|
|
// behavior of Rust 1.12.
|
|
// Storing unknown values in a repr(u16) enum is unsafe. The compiler
|
|
// assumes that there is no undefined discriminant even with a C-like
|
|
// enum, so the exhaustiveness check of a match expression will break.
|
|
// Storing unknown values in a special variant such as Unknown(u16)
|
|
// tends to break backward compatibility. When Tag::VariantFoo is
|
|
// defined in a new version of the library, the old codes using
|
|
// Tag::Unknown(Foo's value) will break.
|
|
|
|
/// A tag of a TIFF field.
|
|
#[derive(Debug)]
|
|
pub struct Tag(pub u16);
|