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889 lines
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889 lines
24 KiB
<!DOCTYPE html>
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<title>utf8 - The Go Programming Language</title>
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<div class="top-heading" id="heading-wide"><a href="http://localhost:6060/">The Go Programming Language</a></div>
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<h1>Package utf8</h1>
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<div id="nav"></div>
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<!--
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Copyright 2009 The Go Authors. All rights reserved.
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Use of this source code is governed by a BSD-style
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license that can be found in the LICENSE file.
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-->
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Note: Static (i.e., not template-generated) href and id
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</script>
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<div id="short-nav">
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<dl>
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<dd><code>import "unicode/utf8"</code></dd>
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</dl>
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<dl>
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<dd><a href="index.html#pkg-overview" class="overviewLink">Overview</a></dd>
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<dd><a href="index.html#pkg-index" class="indexLink">Index</a></dd>
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<div class="expanded">
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<h2 class="toggleButton" title="Click to hide Overview section">Overview ▾</h2>
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<p>
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Package utf8 implements functions and constants to support text encoded in
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UTF-8. It includes functions to translate between runes and UTF-8 byte sequences.
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</p>
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</div>
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<h2 class="toggleButton" title="Click to hide Index section">Index ▾</h2>
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<dl>
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<dd><a href="index.html#pkg-constants">Constants</a></dd>
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<dd><a href="index.html#DecodeLastRune">func DecodeLastRune(p []byte) (r rune, size int)</a></dd>
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<dd><a href="index.html#DecodeLastRuneInString">func DecodeLastRuneInString(s string) (r rune, size int)</a></dd>
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<dd><a href="index.html#DecodeRune">func DecodeRune(p []byte) (r rune, size int)</a></dd>
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<dd><a href="index.html#DecodeRuneInString">func DecodeRuneInString(s string) (r rune, size int)</a></dd>
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<dd><a href="index.html#EncodeRune">func EncodeRune(p []byte, r rune) int</a></dd>
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<dd><a href="index.html#FullRune">func FullRune(p []byte) bool</a></dd>
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<dd><a href="index.html#FullRuneInString">func FullRuneInString(s string) bool</a></dd>
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<dd><a href="index.html#RuneCount">func RuneCount(p []byte) int</a></dd>
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<dd><a href="index.html#RuneCountInString">func RuneCountInString(s string) (n int)</a></dd>
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<dd><a href="index.html#RuneLen">func RuneLen(r rune) int</a></dd>
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<dd><a href="index.html#RuneStart">func RuneStart(b byte) bool</a></dd>
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<dd><a href="index.html#Valid">func Valid(p []byte) bool</a></dd>
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<dd><a href="index.html#ValidRune">func ValidRune(r rune) bool</a></dd>
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<dd><a href="index.html#ValidString">func ValidString(s string) bool</a></dd>
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</dl>
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</div><!-- #manual-nav -->
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<div id="pkg-examples">
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<h4>Examples</h4>
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<dl>
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<dd><a class="exampleLink" href="index.html#example_DecodeLastRune">DecodeLastRune</a></dd>
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<dd><a class="exampleLink" href="index.html#example_DecodeLastRuneInString">DecodeLastRuneInString</a></dd>
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<dd><a class="exampleLink" href="index.html#example_DecodeRune">DecodeRune</a></dd>
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<dd><a class="exampleLink" href="index.html#example_DecodeRuneInString">DecodeRuneInString</a></dd>
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<dd><a class="exampleLink" href="index.html#example_EncodeRune">EncodeRune</a></dd>
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<dd><a class="exampleLink" href="index.html#example_FullRune">FullRune</a></dd>
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<dd><a class="exampleLink" href="index.html#example_FullRuneInString">FullRuneInString</a></dd>
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<dd><a class="exampleLink" href="index.html#example_RuneCount">RuneCount</a></dd>
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<dd><a class="exampleLink" href="index.html#example_RuneCountInString">RuneCountInString</a></dd>
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<dd><a class="exampleLink" href="index.html#example_RuneLen">RuneLen</a></dd>
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<dd><a class="exampleLink" href="index.html#example_RuneStart">RuneStart</a></dd>
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<dd><a class="exampleLink" href="index.html#example_Valid">Valid</a></dd>
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<dd><a class="exampleLink" href="index.html#example_ValidRune">ValidRune</a></dd>
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<dd><a class="exampleLink" href="index.html#example_ValidString">ValidString</a></dd>
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</dl>
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</div>
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<h4>Package files</h4>
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<p>
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<span style="font-size:90%">
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<a href="http://localhost:6060/src/unicode/utf8/utf8.go">utf8.go</a>
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</span>
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</p>
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</div><!-- .expanded -->
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</div><!-- #pkg-index -->
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<div id="pkg-callgraph" class="toggle" style="display: none">
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<div class="collapsed">
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<h2 class="toggleButton" title="Click to show Internal Call Graph section">Internal call graph ▹</h2>
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</div> <!-- .expanded -->
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<div class="expanded">
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<h2 class="toggleButton" title="Click to hide Internal Call Graph section">Internal call graph ▾</h2>
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<p>
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In the call graph viewer below, each node
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is a function belonging to this package
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and its children are the functions it
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calls—perhaps dynamically.
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</p>
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<p>
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The root nodes are the entry points of the
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package: functions that may be called from
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outside the package.
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There may be non-exported or anonymous
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functions among them if they are called
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dynamically from another package.
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</p>
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<p>
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Click a node to visit that function's source code.
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From there you can visit its callers by
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clicking its declaring <code>func</code>
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token.
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</p>
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<p>
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Functions may be omitted if they were
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determined to be unreachable in the
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particular programs or tests that were
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analyzed.
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</p>
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<!-- Zero means show all package entry points. -->
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<ul style="margin-left: 0.5in" id="callgraph-0" class="treeview"></ul>
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</div>
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</div> <!-- #pkg-callgraph -->
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<h2 id="pkg-constants">Constants</h2>
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<pre>const (
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<span id="RuneError">RuneError</span> = '\uFFFD' <span class="comment">// the "error" Rune or "Unicode replacement character"</span>
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<span id="RuneSelf">RuneSelf</span> = 0x80 <span class="comment">// characters below Runeself are represented as themselves in a single byte.</span>
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<span id="MaxRune">MaxRune</span> = '\U0010FFFF' <span class="comment">// Maximum valid Unicode code point.</span>
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<span id="UTFMax">UTFMax</span> = 4 <span class="comment">// maximum number of bytes of a UTF-8 encoded Unicode character.</span>
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)</pre>
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<p>
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Numbers fundamental to the encoding.
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</p>
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<h2 id="DecodeLastRune">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=8153:8201#L239">DecodeLastRune</a></h2>
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<pre>func DecodeLastRune(p []<a href="../../builtin/index.html#byte">byte</a>) (r <a href="../../builtin/index.html#rune">rune</a>, size <a href="../../builtin/index.html#int">int</a>)</pre>
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<p>
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DecodeLastRune unpacks the last UTF-8 encoding in p and returns the rune and
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its width in bytes. If p is empty it returns (RuneError, 0). Otherwise, if
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the encoding is invalid, it returns (RuneError, 1). Both are impossible
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results for correct, non-empty UTF-8.
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</p>
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<p>
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An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
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out of range, or is not the shortest possible UTF-8 encoding for the
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value. No other validation is performed.
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</p>
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<div id="example_DecodeLastRune" class="toggle">
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<div class="collapsed">
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<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
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</div>
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<div class="expanded">
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<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
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<p>Code:</p>
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<pre class="code">b := []byte("Hello, 世界")
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for len(b) > 0 {
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r, size := utf8.DecodeLastRune(b)
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fmt.Printf("%c %v\n", r, size)
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b = b[:len(b)-size]
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}
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<span class="comment"></pre>
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<p>Output:</p>
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<pre class="output">界 3
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世 3
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1
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, 1
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o 1
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l 1
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l 1
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e 1
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H 1
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</pre>
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</div>
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</div>
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<h2 id="DecodeLastRuneInString">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=9163:9219#L279">DecodeLastRuneInString</a></h2>
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<pre>func DecodeLastRuneInString(s <a href="../../builtin/index.html#string">string</a>) (r <a href="../../builtin/index.html#rune">rune</a>, size <a href="../../builtin/index.html#int">int</a>)</pre>
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<p>
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DecodeLastRuneInString is like DecodeLastRune but its input is a string. If
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s is empty it returns (RuneError, 0). Otherwise, if the encoding is invalid,
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it returns (RuneError, 1). Both are impossible results for correct,
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non-empty UTF-8.
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</p>
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<p>
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An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
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out of range, or is not the shortest possible UTF-8 encoding for the
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value. No other validation is performed.
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</p>
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<div id="example_DecodeLastRuneInString" class="toggle">
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<div class="collapsed">
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<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
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</div>
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<div class="expanded">
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<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
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<p>Code:</p>
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<pre class="code">str := "Hello, 世界"
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for len(str) > 0 {
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r, size := utf8.DecodeLastRuneInString(str)
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fmt.Printf("%c %v\n", r, size)
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str = str[:len(str)-size]
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}
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<span class="comment"></pre>
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<p>Output:</p>
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<pre class="output">界 3
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世 3
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1
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, 1
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o 1
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l 1
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l 1
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e 1
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H 1
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</pre>
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</div>
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</div>
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<h2 id="DecodeRune">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=5307:5351#L143">DecodeRune</a></h2>
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<pre>func DecodeRune(p []<a href="../../builtin/index.html#byte">byte</a>) (r <a href="../../builtin/index.html#rune">rune</a>, size <a href="../../builtin/index.html#int">int</a>)</pre>
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<p>
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DecodeRune unpacks the first UTF-8 encoding in p and returns the rune and
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its width in bytes. If p is empty it returns (RuneError, 0). Otherwise, if
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the encoding is invalid, it returns (RuneError, 1). Both are impossible
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results for correct, non-empty UTF-8.
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</p>
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<p>
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An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
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out of range, or is not the shortest possible UTF-8 encoding for the
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value. No other validation is performed.
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</p>
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<div id="example_DecodeRune" class="toggle">
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<div class="collapsed">
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<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
|
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</div>
|
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<div class="expanded">
|
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<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
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|
|
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<p>Code:</p>
|
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<pre class="code">b := []byte("Hello, 世界")
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for len(b) > 0 {
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r, size := utf8.DecodeRune(b)
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fmt.Printf("%c %v\n", r, size)
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b = b[size:]
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}
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<span class="comment"></pre>
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<p>Output:</p>
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<pre class="output">H 1
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e 1
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l 1
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l 1
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o 1
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, 1
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1
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世 3
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界 3
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</pre>
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</div>
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</div>
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<h2 id="DecodeRuneInString">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=6710:6762#L191">DecodeRuneInString</a></h2>
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<pre>func DecodeRuneInString(s <a href="../../builtin/index.html#string">string</a>) (r <a href="../../builtin/index.html#rune">rune</a>, size <a href="../../builtin/index.html#int">int</a>)</pre>
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<p>
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DecodeRuneInString is like DecodeRune but its input is a string. If s is
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empty it returns (RuneError, 0). Otherwise, if the encoding is invalid, it
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returns (RuneError, 1). Both are impossible results for correct, non-empty
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UTF-8.
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</p>
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<p>
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An encoding is invalid if it is incorrect UTF-8, encodes a rune that is
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out of range, or is not the shortest possible UTF-8 encoding for the
|
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value. No other validation is performed.
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</p>
|
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|
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<div id="example_DecodeRuneInString" class="toggle">
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<div class="collapsed">
|
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<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
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</div>
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<div class="expanded">
|
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<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
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|
|
|
|
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<p>Code:</p>
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<pre class="code">str := "Hello, 世界"
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for len(str) > 0 {
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r, size := utf8.DecodeRuneInString(str)
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fmt.Printf("%c %v\n", r, size)
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str = str[size:]
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}
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<span class="comment"></pre>
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<p>Output:</p>
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<pre class="output">H 1
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e 1
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l 1
|
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l 1
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o 1
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, 1
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1
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世 3
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界 3
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</pre>
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</div>
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</div>
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<h2 id="EncodeRune">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=10279:10316#L333">EncodeRune</a></h2>
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<pre>func EncodeRune(p []<a href="../../builtin/index.html#byte">byte</a>, r <a href="../../builtin/index.html#rune">rune</a>) <a href="../../builtin/index.html#int">int</a></pre>
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<p>
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EncodeRune writes into p (which must be large enough) the UTF-8 encoding of the rune.
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It returns the number of bytes written.
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</p>
|
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<div id="example_EncodeRune" class="toggle">
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<div class="collapsed">
|
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<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
|
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</div>
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<div class="expanded">
|
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<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
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|
|
|
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<p>Code:</p>
|
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<pre class="code">r := '世'
|
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buf := make([]byte, 3)
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|
|
n := utf8.EncodeRune(buf, r)
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fmt.Println(buf)
|
|
fmt.Println(n)
|
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<span class="comment"></pre>
|
|
|
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<p>Output:</p>
|
|
<pre class="output">[228 184 150]
|
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3
|
|
</pre>
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</div>
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</div>
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<h2 id="FullRune">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=3999:4027#L92">FullRune</a></h2>
|
|
<pre>func FullRune(p []<a href="../../builtin/index.html#byte">byte</a>) <a href="../../builtin/index.html#bool">bool</a></pre>
|
|
<p>
|
|
FullRune reports whether the bytes in p begin with a full UTF-8 encoding of a rune.
|
|
An invalid encoding is considered a full Rune since it will convert as a width-1 error rune.
|
|
</p>
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|
|
|
<div id="example_FullRune" class="toggle">
|
|
<div class="collapsed">
|
|
<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
|
|
</div>
|
|
<div class="expanded">
|
|
<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
|
|
|
|
|
|
|
|
<p>Code:</p>
|
|
<pre class="code">buf := []byte{228, 184, 150} <span class="comment">// 世</span>
|
|
fmt.Println(utf8.FullRune(buf))
|
|
fmt.Println(utf8.FullRune(buf[:2]))
|
|
<span class="comment"></pre>
|
|
|
|
<p>Output:</p>
|
|
<pre class="output">true
|
|
false
|
|
</pre>
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|
|
|
|
|
</div>
|
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</div>
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<h2 id="FullRuneInString">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=4448:4484#L114">FullRuneInString</a></h2>
|
|
<pre>func FullRuneInString(s <a href="../../builtin/index.html#string">string</a>) <a href="../../builtin/index.html#bool">bool</a></pre>
|
|
<p>
|
|
FullRuneInString is like FullRune but its input is a string.
|
|
</p>
|
|
|
|
<div id="example_FullRuneInString" class="toggle">
|
|
<div class="collapsed">
|
|
<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
|
|
</div>
|
|
<div class="expanded">
|
|
<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
|
|
|
|
|
|
|
|
<p>Code:</p>
|
|
<pre class="code">str := "世"
|
|
fmt.Println(utf8.FullRuneInString(str))
|
|
fmt.Println(utf8.FullRuneInString(str[:2]))
|
|
<span class="comment"></pre>
|
|
|
|
<p>Output:</p>
|
|
<pre class="output">true
|
|
false
|
|
</pre>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<h2 id="RuneCount">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=11033:11061#L362">RuneCount</a></h2>
|
|
<pre>func RuneCount(p []<a href="../../builtin/index.html#byte">byte</a>) <a href="../../builtin/index.html#int">int</a></pre>
|
|
<p>
|
|
RuneCount returns the number of runes in p. Erroneous and short
|
|
encodings are treated as single runes of width 1 byte.
|
|
</p>
|
|
|
|
<div id="example_RuneCount" class="toggle">
|
|
<div class="collapsed">
|
|
<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
|
|
</div>
|
|
<div class="expanded">
|
|
<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
|
|
|
|
|
|
|
|
<p>Code:</p>
|
|
<pre class="code">buf := []byte("Hello, 世界")
|
|
fmt.Println("bytes =", len(buf))
|
|
fmt.Println("runes =", utf8.RuneCount(buf))
|
|
<span class="comment"></pre>
|
|
|
|
<p>Output:</p>
|
|
<pre class="output">bytes = 13
|
|
runes = 9
|
|
</pre>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<h2 id="RuneCountInString">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=11705:11745#L399">RuneCountInString</a></h2>
|
|
<pre>func RuneCountInString(s <a href="../../builtin/index.html#string">string</a>) (n <a href="../../builtin/index.html#int">int</a>)</pre>
|
|
<p>
|
|
RuneCountInString is like RuneCount but its input is a string.
|
|
</p>
|
|
|
|
<div id="example_RuneCountInString" class="toggle">
|
|
<div class="collapsed">
|
|
<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
|
|
</div>
|
|
<div class="expanded">
|
|
<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
|
|
|
|
|
|
|
|
<p>Code:</p>
|
|
<pre class="code">str := "Hello, 世界"
|
|
fmt.Println("bytes =", len(str))
|
|
fmt.Println("runes =", utf8.RuneCountInString(str))
|
|
<span class="comment"></pre>
|
|
|
|
<p>Output:</p>
|
|
<pre class="output">bytes = 13
|
|
runes = 9
|
|
</pre>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<h2 id="RuneLen">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=9883:9907#L313">RuneLen</a></h2>
|
|
<pre>func RuneLen(r <a href="../../builtin/index.html#rune">rune</a>) <a href="../../builtin/index.html#int">int</a></pre>
|
|
<p>
|
|
RuneLen returns the number of bytes required to encode the rune.
|
|
It returns -1 if the rune is not a valid value to encode in UTF-8.
|
|
</p>
|
|
|
|
<div id="example_RuneLen" class="toggle">
|
|
<div class="collapsed">
|
|
<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
|
|
</div>
|
|
<div class="expanded">
|
|
<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
|
|
|
|
|
|
|
|
<p>Code:</p>
|
|
<pre class="code">fmt.Println(utf8.RuneLen('a'))
|
|
fmt.Println(utf8.RuneLen('界'))
|
|
<span class="comment"></pre>
|
|
|
|
<p>Output:</p>
|
|
<pre class="output">1
|
|
3
|
|
</pre>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<h2 id="RuneStart">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=12485:12512#L436">RuneStart</a></h2>
|
|
<pre>func RuneStart(b <a href="../../builtin/index.html#byte">byte</a>) <a href="../../builtin/index.html#bool">bool</a></pre>
|
|
<p>
|
|
RuneStart reports whether the byte could be the first byte of an encoded,
|
|
possibly invalid rune. Second and subsequent bytes always have the top two
|
|
bits set to 10.
|
|
</p>
|
|
|
|
<div id="example_RuneStart" class="toggle">
|
|
<div class="collapsed">
|
|
<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
|
|
</div>
|
|
<div class="expanded">
|
|
<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
|
|
|
|
|
|
|
|
<p>Code:</p>
|
|
<pre class="code">buf := []byte("a界")
|
|
fmt.Println(utf8.RuneStart(buf[0]))
|
|
fmt.Println(utf8.RuneStart(buf[1]))
|
|
fmt.Println(utf8.RuneStart(buf[2]))
|
|
<span class="comment"></pre>
|
|
|
|
<p>Output:</p>
|
|
<pre class="output">true
|
|
true
|
|
false
|
|
</pre>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<h2 id="Valid">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=12615:12640#L439">Valid</a></h2>
|
|
<pre>func Valid(p []<a href="../../builtin/index.html#byte">byte</a>) <a href="../../builtin/index.html#bool">bool</a></pre>
|
|
<p>
|
|
Valid reports whether p consists entirely of valid UTF-8-encoded runes.
|
|
</p>
|
|
|
|
<div id="example_Valid" class="toggle">
|
|
<div class="collapsed">
|
|
<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
|
|
</div>
|
|
<div class="expanded">
|
|
<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
|
|
|
|
|
|
|
|
<p>Code:</p>
|
|
<pre class="code">valid := []byte("Hello, 世界")
|
|
invalid := []byte{0xff, 0xfe, 0xfd}
|
|
|
|
fmt.Println(utf8.Valid(valid))
|
|
fmt.Println(utf8.Valid(invalid))
|
|
<span class="comment"></pre>
|
|
|
|
<p>Output:</p>
|
|
<pre class="output">true
|
|
false
|
|
</pre>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<h2 id="ValidRune">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=14008:14035#L504">ValidRune</a></h2>
|
|
<pre>func ValidRune(r <a href="../../builtin/index.html#rune">rune</a>) <a href="../../builtin/index.html#bool">bool</a></pre>
|
|
<p>
|
|
ValidRune reports whether r can be legally encoded as UTF-8.
|
|
Code points that are out of range or a surrogate half are illegal.
|
|
</p>
|
|
|
|
<div id="example_ValidRune" class="toggle">
|
|
<div class="collapsed">
|
|
<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
|
|
</div>
|
|
<div class="expanded">
|
|
<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
|
|
|
|
|
|
|
|
<p>Code:</p>
|
|
<pre class="code">valid := 'a'
|
|
invalid := rune(0xfffffff)
|
|
|
|
fmt.Println(utf8.ValidRune(valid))
|
|
fmt.Println(utf8.ValidRune(invalid))
|
|
<span class="comment"></pre>
|
|
|
|
<p>Output:</p>
|
|
<pre class="output">true
|
|
false
|
|
</pre>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<h2 id="ValidString">func <a href="http://localhost:6060/src/unicode/utf8/utf8.go?s=13282:13313#L471">ValidString</a></h2>
|
|
<pre>func ValidString(s <a href="../../builtin/index.html#string">string</a>) <a href="../../builtin/index.html#bool">bool</a></pre>
|
|
<p>
|
|
ValidString reports whether s consists entirely of valid UTF-8-encoded runes.
|
|
</p>
|
|
|
|
<div id="example_ValidString" class="toggle">
|
|
<div class="collapsed">
|
|
<p class="exampleHeading toggleButton">▹ <span class="text">Example</span></p>
|
|
</div>
|
|
<div class="expanded">
|
|
<p class="exampleHeading toggleButton">▾ <span class="text">Example</span></p>
|
|
|
|
|
|
|
|
<p>Code:</p>
|
|
<pre class="code">valid := "Hello, 世界"
|
|
invalid := string([]byte{0xff, 0xfe, 0xfd})
|
|
|
|
fmt.Println(utf8.ValidString(valid))
|
|
fmt.Println(utf8.ValidString(invalid))
|
|
<span class="comment"></pre>
|
|
|
|
<p>Output:</p>
|
|
<pre class="output">true
|
|
false
|
|
</pre>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
|
|
|
|
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|
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|
|
<div id="footer">
|
|
Build version go1.6.<br>
|
|
Except as <a href="https://developers.google.com/site-policies#restrictions">noted</a>,
|
|
the content of this page is licensed under the
|
|
Creative Commons Attribution 3.0 License,
|
|
and code is licensed under a <a href="http://localhost:6060/LICENSE">BSD license</a>.<br>
|
|
<a href="http://localhost:6060/doc/tos.html">Terms of Service</a> |
|
|
<a href="http://www.google.com/intl/en/policies/privacy/">Privacy Policy</a>
|
|
</div>
|
|
|
|
</div><!-- .container -->
|
|
</div><!-- #page -->
|
|
|
|
<!-- TODO(adonovan): load these from <head> using "defer" attribute? -->
|
|
<script type="text/javascript" src="../../../lib/godoc/jquery.js"></script>
|
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<script type="text/javascript" src="../../../lib/godoc/jquery.treeview.js"></script>
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<script type="text/javascript" src="../../../lib/godoc/jquery.treeview.edit.js"></script>
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<script type="text/javascript" src="../../../lib/godoc/godocs.js"></script>
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