Skip to content
体验新版
项目
组织
正在加载...
登录
切换导航
打开侧边栏
int
Rust
提交
e0072e39
R
Rust
项目概览
int
/
Rust
大约 1 年 前同步成功
通知
1
Star
0
Fork
0
代码
文件
提交
分支
Tags
贡献者
分支图
Diff
Issue
0
列表
看板
标记
里程碑
合并请求
0
DevOps
流水线
流水线任务
计划
Wiki
0
Wiki
分析
仓库
DevOps
项目成员
Pages
R
Rust
项目概览
项目概览
详情
发布
仓库
仓库
文件
提交
分支
标签
贡献者
分支图
比较
Issue
0
Issue
0
列表
看板
标记
里程碑
合并请求
0
合并请求
0
Pages
DevOps
DevOps
流水线
流水线任务
计划
分析
分析
仓库分析
DevOps
Wiki
0
Wiki
成员
成员
收起侧边栏
关闭侧边栏
动态
分支图
创建新Issue
流水线任务
提交
Issue看板
体验新版 GitCode,发现更多精彩内容 >>
提交
e0072e39
编写于
12月 19, 2012
作者:
G
Graydon Hoare
浏览文件
操作
浏览文件
下载
电子邮件补丁
差异文件
doc: structure expressions. cc: #4217
上级
46766974
变更
1
隐藏空白更改
内联
并排
Showing
1 changed file
with
37 addition
and
2 deletion
+37
-2
doc/rust.md
doc/rust.md
+37
-2
未找到文件。
doc/rust.md
浏览文件 @
e0072e39
...
...
@@ -1503,6 +1503,39 @@ values.
("a", 4u, true);
~~~~~~~~
### Structure expressions
~~~~~~~~
{.ebnf .gram}
struct_expr : expr_path '{' ident ':' expr
[ ',' ident ':' expr ] *
[ ".." expr ] '}'
~~~~~~~~
A _structure expression_ consists of the
[
path
](
#paths
)
of a
[
structure item
](
#structures
)
,
followed by a brace-enclosed list of one or more comma-separated name-value pairs,
providing the field values of a new instance of the structure.
A field name can be any identifier, and is separated from its value expression by a colon.
To indicate that a field is mutable, the
`mut`
keyword is written before its name.
The following are examples of structure expressions:
~~~~
Point {x: 10f, y: 20f};
game::User {name: "Joe", age: 35u, mut score: 100_000};
~~~~
A structure expression forms a new value of the named structure type.
A structure expression can terminate with the syntax
`..`
followed by an expression to denote a functional update.
The expression following
`..`
(the base) must be of the same structure type as the new structure type being formed.
A new structure will be created, of the same type as the base expression, with the given values for the fields that were explicitly specified,
and the values in the base record for all other fields.
~~~~
let base = Point3d {x: 1, y: 2, z: 3};
Point3d {y: 0, z: 10, .. base};
~~~~
### Record expressions
~~~~~~~~
{.ebnf .gram}
...
...
@@ -1511,9 +1544,11 @@ rec_expr : '{' ident ':' expr
[ ".." expr ] '}'
~~~~~~~~
> **Note:** In future versions of Rust, record expressions and [record types](#record-types) will be removed.
A
[
_record_
](
#record-types
)
_expression_
is one or more comma-separated
name-value pairs enclosed by braces. A fieldname can be any identifier
(including keywords),
and is separated from its value expression by a
name-value pairs enclosed by braces. A fieldname can be any identifier
,
and is separated from its value expression by a
colon. To indicate that a field is mutable, the
`mut`
keyword is
written before its name.
...
...
编辑
预览
Markdown
is supported
0%
请重试
或
添加新附件
.
添加附件
取消
You are about to add
0
people
to the discussion. Proceed with caution.
先完成此消息的编辑!
取消
想要评论请
注册
或
登录