| ... | ... | @@ -7274,46 +7274,27 @@ fn readU32Be() u32 {} |
| 7274 | 7274 | </ul> |
| 7275 | 7275 | {#header_close#} |
| 7276 | 7276 | {#header_close#} |
| 7277 | |
| 7277 | 7278 | {#header_open|Source Encoding#} |
| 7278 | | <p>Zig source code is encoded in UTF-8. An invalid UTF-8 byte sequence results in a compile error.</p> |
| 7279 | | <p>Throughout all zig source code (including in comments), some code points are never allowed:</p> |
| 7279 | <p>Zig source code is UTF-8 encoded. Invalid UTF-8 byte sequences are not allowed anywhere.</p> |
| 7280 | <p>Some code points are never allowed, even in {#link|Comments#}:</p> |
| 7280 | 7281 | <ul> |
| 7281 | | <li>Ascii control characters, except for U+000a (LF), U+000d (CR), and U+0009 (HT): U+0000 - U+0008, U+000b - U+000c, U+000e - U+0001f, U+007f.</li> |
| 7282 | | <li>Non-Ascii Unicode line endings: U+0085 (NEL), U+2028 (LS), U+2029 (PS).</li> |
| 7282 | <li>ASCII control characters, except for U+000a (LF): U+0000...U+0009, U+000b...U+0001f, U+007f.</li> |
| 7283 | <li>Non-ASCII Unicode line endings: U+0085 (NEL), U+2028 (LS), U+2029 (PS).</li> |
| 7284 | <li>Byte order marks: U+FEFF (BOM).</li> |
| 7283 | 7285 | </ul> |
| 7284 | 7286 | <p> |
| 7285 | | LF (byte value 0x0a, code point U+000a, {#syntax#}'\n'{#endsyntax#}) is the line terminator in Zig source code. |
| 7286 | | This byte value terminates every line of zig source code except the last line of the file. |
| 7287 | | It is recommended that non-empty source files end with an empty line, which means the last byte would be 0x0a (LF). |
| 7288 | | </p> |
| 7289 | | <p> |
| 7290 | | Each LF may be immediately preceded by a single CR (byte value 0x0d, code point U+000d, {#syntax#}'\r'{#endsyntax#}) |
| 7291 | | to form a Windows style line ending, but this is discouraged. Note that in multiline strings, CRLF sequences will |
| 7292 | | be encoded as LF when compiled into a zig program. |
| 7293 | | A CR in any other context is not allowed. |
| 7294 | | </p> |
| 7295 | | <p> |
| 7296 | | HT hard tabs (byte value 0x09, code point U+0009, {#syntax#}'\t'{#endsyntax#}) are interchangeable with |
| 7297 | | SP spaces (byte value 0x20, code point U+0020, {#syntax#}' '{#endsyntax#}) as a token separator, |
| 7298 | | but use of hard tabs is discouraged. See {#link|Grammar#}. |
| 7299 | | </p> |
| 7300 | | <p> |
| 7301 | | For compatibility with other tools, the compiler ignores a UTF-8-encoded byte order mark (U+FEFF) |
| 7302 | | if it is the first Unicode code point in the source text. A byte order mark is not allowed anywhere else in the source. |
| 7303 | | </p> |
| 7304 | | <p> |
| 7305 | | Note that running <kbd>zig fmt</kbd> on a source file will implement all recommendations mentioned here. |
| 7306 | | </p> |
| 7307 | | <p> |
| 7308 | | Note that a tool reading Zig source code can make assumptions if the source code is assumed to be correct Zig code. |
| 7309 | | For example, when identifying the ends of lines, a tool can use a naive search such as <code>/\n/</code>, |
| 7310 | | or an <a href="https://msdn.microsoft.com/en-us/library/dd409797.aspx">advanced</a> |
| 7311 | | search such as <code>/\r\n?|[\n\u0085\u2028\u2029]/</code>, and in either case line endings will be correctly identified. |
| 7312 | | For another example, when identifying the whitespace before the first token on a line, |
| 7313 | | a tool can either use a naive search such as <code>/[ \t]/</code>, |
| 7314 | | or an <a href="https://tc39.es/ecma262/#sec-characterclassescape">advanced</a> search such as <code>/\s/</code>, |
| 7315 | | and in either case whitespace will be correctly identified. |
| 7316 | | </p> |
| 7287 | LF (byte value 0x0a, code point U+000a, {#syntax#}'\n'{#endsyntax#}) is |
| 7288 | the line terminator in Zig source code. This byte value terminates every |
| 7289 | line of Zig source code, including last line of the file. |
| 7290 | </p> |
| 7291 | <p>These conservative rules mean that third party tools reading |
| 7292 | already-validated Zig source code may make simplifying assumptions, such |
| 7293 | as naively separating lines based on {#syntax#}'\n'{#endsyntax#}. |
| 7294 | However, tooling such as <kbd>zig fmt</kbd> provides convenience |
| 7295 | functionality to convert invalid source encodings to valid source |
| 7296 | encodings, for instance by stripping byte order marks and carriage |
| 7297 | returns.</p> |
| 7317 | 7298 | {#header_close#} |
| 7318 | 7299 | |
| 7319 | 7300 | {#header_open|Keyword Reference#} |
Andrew Kelley <andrew@ziglang.org> 2026-08-20 17:33:16-07:00