encoding.qmd

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pagetitle: Character Encoding
---

# Character Encoding

# 字符编码

本节译者：李泓玮

## Content characters

## 内容字符

The content of a Stan program must be coded in ASCII.  All identifiers
must consist of only ASCII alpha-numeric characters and the underscore
character.  All arithmetic operators and punctuation must be coded in
ASCII.

Stan 程序的内容必须用 ASCII 编码。所有标识符必须仅由 ASCII 字母数字字符和下划线字符组成。所有的算术运算符和标点符号都必须用 ASCII 编码。

### Compatibility with Latin-1 and UTF-8 {-}

### 兼容 Latin-1 和 UTF-8 {-}

The UTF-8 encoding of Unicode and the Latin-1 (ISO-8859-1) encoding
share the first 128 code points with ASCII and thus cannot be
distinguished from ASCII.  That means you can set editors, etc., to
use UTF-8 or Latin-1 (or the other Latin-n variants) without worrying
that the content of a Stan program will be destroyed.

Unicode 的 UTF-8 编码和 Latin-1（ISO-8859-1） 编码与 ASCII 共享前128个码点，因此无法与 ASCII 区分开来。这意味着你可以设置编辑器等来使用 UTF-8 或 Latin-1（或其他 Latin-n 变体），而不必担心 Stan 程序的内容会被破坏。

## Comment characters

## 注释字符

Any bytes on a line after a line-comment sequence (`//` or
`#`) are ignored up until the ASCII newline character
(`\n`).  They may thus be written in any character encoding which
is convenient.

行注释序列（ `//`  或  `#` ）之后的任何字节都会被忽略，直到 ASCII 换行符（ `\n` ）。因此，它们可以写成任何方便的字符编码。

Any content after a block comment open sequence in ASCII (`/*`)
up to the closing block comment (`*/`) is ignored, and thus may
also be written in whatever character set is convenient.

从块注释开始（ `/*` ）到块注释结束（ `*/` ）之间的任何内容都会被忽略，因此也可以用任何方便的字符集来编写。

## String literals

## 字符串字面量

The raw byte sequence within a string literal is escaped according 
to the C++ standard. In particular, this means that UTF-8 encoded 
strings are supported, however they are not tested for invalid byte 
sequences. A `print` or `reject` statement should properly display 
Unicode characters if your terminal supports the encoding used in the
input. In other words, Stan simply preserves any string of bytes between two double quotes (`"`) when passing to C++. On compliant terminals, this allows the use of glyphs and other characters from encodings such as UTF-8 that fall outside the ASCII-compatible range.

字符串字面量中的原始字节序列根据 C++ 标准进行转义。特别地，这意味着 UTF-8 编码的字符串是受支持的，系统不会检测它们是否是无效的字节序列。如果你的终端支持输入中使用的编码，那么 `print` 或 `reject` 语句应该正确地显示 Unicode 字符。换句话说，Stan 在传递给 C++ 时，只保留两个双引号（`"`）之间的任何字节串。在兼容的终端上，这允许使用符号（glyph）和其他编码的字符，例如超出 ASCII 兼容范围的 UTF-8 编码。

ASCII is the recommended encoding for maximum portability, because it encodes
the ASCII characters (Unicode code points 0--127) using the same sequence of
bytes as the UTF-8 encoding of Unicode and common ISO-8859 extensions of Latin.

为了获得最大的可移植性，推荐使用 ASCII 编码，因为它编码 ASCII 字符（ Unicode 码点0 -- 127）时使用的字节序列与 Unicode 的 UTF-8 编码和常见的 Latin ISO-8859 扩展相同。