File: C:/Ruby27-x64/share/doc/ruby/html/Gem/Text.html
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<h3>Methods</h3>
<ul class="link-list" role="directory">
<li ><a href="#method-i-clean_text">#clean_text</a>
<li ><a href="#method-i-format_text">#format_text</a>
<li ><a href="#method-i-levenshtein_distance">#levenshtein_distance</a>
<li ><a href="#method-i-truncate_text">#truncate_text</a>
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<main role="main" aria-labelledby="module-Gem::Text">
<h1 id="module-Gem::Text" class="module">
module Gem::Text
</h1>
<section class="description">
<p>A collection of text-wrangling methods</p>
</section>
<section id="5Buntitled-5D" class="documentation-section">
<section id="public-instance-5Buntitled-5D-method-details" class="method-section">
<header>
<h3>Public Instance Methods</h3>
</header>
<div id="method-i-clean_text" class="method-detail ">
<div class="method-heading">
<span class="method-name">clean_text</span><span
class="method-args">(text)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Remove any non-printable characters and make the text suitable for printing.</p>
<div class="method-source-code" id="clean_text-source">
<pre><span class="ruby-comment"># File lib/rubygems/text.rb, line 11</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">clean_text</span>(<span class="ruby-identifier">text</span>)
<span class="ruby-identifier">text</span>.<span class="ruby-identifier">gsub</span>(<span class="ruby-regexp">/[\000-\b\v-\f\016-\037\177]/</span>, <span class="ruby-string">"."</span>.<span class="ruby-identifier">freeze</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-format_text" class="method-detail ">
<div class="method-heading">
<span class="method-name">format_text</span><span
class="method-args">(text, wrap, indent=0)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Wraps <code>text</code> to <code>wrap</code> characters and optionally indents by <code>indent</code> characters</p>
<div class="method-source-code" id="format_text-source">
<pre><span class="ruby-comment"># File lib/rubygems/text.rb, line 25</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">format_text</span>(<span class="ruby-identifier">text</span>, <span class="ruby-identifier">wrap</span>, <span class="ruby-identifier">indent</span>=<span class="ruby-value">0</span>)
<span class="ruby-identifier">result</span> = []
<span class="ruby-identifier">work</span> = <span class="ruby-identifier">clean_text</span>(<span class="ruby-identifier">text</span>)
<span class="ruby-keyword">while</span> <span class="ruby-identifier">work</span>.<span class="ruby-identifier">length</span> <span class="ruby-operator">></span> <span class="ruby-identifier">wrap</span> <span class="ruby-keyword">do</span>
<span class="ruby-keyword">if</span> <span class="ruby-identifier">work</span> <span class="ruby-operator">=~</span> <span class="ruby-regexp">/^(.{0,#{wrap}})[ \n]/</span>
<span class="ruby-identifier">result</span> <span class="ruby-operator"><<</span> <span class="ruby-node">$1</span>.<span class="ruby-identifier">rstrip</span>
<span class="ruby-identifier">work</span>.<span class="ruby-identifier">slice!</span>(<span class="ruby-value">0</span>, <span class="ruby-node">$&</span>.<span class="ruby-identifier">length</span>)
<span class="ruby-keyword">else</span>
<span class="ruby-identifier">result</span> <span class="ruby-operator"><<</span> <span class="ruby-identifier">work</span>.<span class="ruby-identifier">slice!</span>(<span class="ruby-value">0</span>, <span class="ruby-identifier">wrap</span>)
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span>
<span class="ruby-identifier">result</span> <span class="ruby-operator"><<</span> <span class="ruby-identifier">work</span> <span class="ruby-keyword">if</span> <span class="ruby-identifier">work</span>.<span class="ruby-identifier">length</span>.<span class="ruby-identifier">nonzero?</span>
<span class="ruby-identifier">result</span>.<span class="ruby-identifier">join</span>(<span class="ruby-string">"\n"</span>).<span class="ruby-identifier">gsub</span>(<span class="ruby-regexp">/^/</span>, <span class="ruby-string">" "</span> <span class="ruby-operator">*</span> <span class="ruby-identifier">indent</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-levenshtein_distance" class="method-detail ">
<div class="method-heading">
<span class="method-name">levenshtein_distance</span><span
class="method-args">(str1, str2)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>This code is based directly on the <a href="Text.html"><code>Text</code></a> gem implementation Returns a value representing the “cost” of transforming str1 into str2</p>
<div class="method-source-code" id="levenshtein_distance-source">
<pre><span class="ruby-comment"># File lib/rubygems/text.rb, line 54</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">levenshtein_distance</span>(<span class="ruby-identifier">str1</span>, <span class="ruby-identifier">str2</span>)
<span class="ruby-identifier">s</span> = <span class="ruby-identifier">str1</span>
<span class="ruby-identifier">t</span> = <span class="ruby-identifier">str2</span>
<span class="ruby-identifier">n</span> = <span class="ruby-identifier">s</span>.<span class="ruby-identifier">length</span>
<span class="ruby-identifier">m</span> = <span class="ruby-identifier">t</span>.<span class="ruby-identifier">length</span>
<span class="ruby-keyword">return</span> <span class="ruby-identifier">m</span> <span class="ruby-keyword">if</span> (<span class="ruby-value">0</span> <span class="ruby-operator">==</span> <span class="ruby-identifier">n</span>)
<span class="ruby-keyword">return</span> <span class="ruby-identifier">n</span> <span class="ruby-keyword">if</span> (<span class="ruby-value">0</span> <span class="ruby-operator">==</span> <span class="ruby-identifier">m</span>)
<span class="ruby-identifier">d</span> = (<span class="ruby-value">0</span><span class="ruby-operator">..</span><span class="ruby-identifier">m</span>).<span class="ruby-identifier">to_a</span>
<span class="ruby-identifier">x</span> = <span class="ruby-keyword">nil</span>
<span class="ruby-identifier">str1</span>.<span class="ruby-identifier">each_char</span>.<span class="ruby-identifier">each_with_index</span> <span class="ruby-keyword">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">char1</span>,<span class="ruby-identifier">i</span><span class="ruby-operator">|</span>
<span class="ruby-identifier">e</span> = <span class="ruby-identifier">i</span> <span class="ruby-operator">+</span> <span class="ruby-value">1</span>
<span class="ruby-identifier">str2</span>.<span class="ruby-identifier">each_char</span>.<span class="ruby-identifier">each_with_index</span> <span class="ruby-keyword">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">char2</span>,<span class="ruby-identifier">j</span><span class="ruby-operator">|</span>
<span class="ruby-identifier">cost</span> = (<span class="ruby-identifier">char1</span> <span class="ruby-operator">==</span> <span class="ruby-identifier">char2</span>) <span class="ruby-operator">?</span> <span class="ruby-value">0</span> <span class="ruby-operator">:</span> <span class="ruby-value">1</span>
<span class="ruby-identifier">x</span> = <span class="ruby-identifier">min3</span>(
<span class="ruby-identifier">d</span>[<span class="ruby-identifier">j</span> <span class="ruby-operator">+</span> <span class="ruby-value">1</span>] <span class="ruby-operator">+</span> <span class="ruby-value">1</span>, <span class="ruby-comment"># insertion</span>
<span class="ruby-identifier">e</span> <span class="ruby-operator">+</span> <span class="ruby-value">1</span>, <span class="ruby-comment"># deletion</span>
<span class="ruby-identifier">d</span>[<span class="ruby-identifier">j</span>] <span class="ruby-operator">+</span> <span class="ruby-identifier">cost</span> <span class="ruby-comment"># substitution</span>
)
<span class="ruby-identifier">d</span>[<span class="ruby-identifier">j</span>] = <span class="ruby-identifier">e</span>
<span class="ruby-identifier">e</span> = <span class="ruby-identifier">x</span>
<span class="ruby-keyword">end</span>
<span class="ruby-identifier">d</span>[<span class="ruby-identifier">m</span>] = <span class="ruby-identifier">x</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">return</span> <span class="ruby-identifier">x</span>
<span class="ruby-keyword">end</span></pre>
</div>
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<div id="method-i-truncate_text" class="method-detail ">
<div class="method-heading">
<span class="method-name">truncate_text</span><span
class="method-args">(text, description, max_length = 100_000)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<div class="method-source-code" id="truncate_text-source">
<pre><span class="ruby-comment"># File lib/rubygems/text.rb, line 15</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">truncate_text</span>(<span class="ruby-identifier">text</span>, <span class="ruby-identifier">description</span>, <span class="ruby-identifier">max_length</span> = <span class="ruby-value">100_000</span>)
<span class="ruby-identifier">raise</span> <span class="ruby-constant">ArgumentError</span>, <span class="ruby-string">"max_length must be positive"</span> <span class="ruby-keyword">unless</span> <span class="ruby-identifier">max_length</span> <span class="ruby-operator">></span> <span class="ruby-value">0</span>
<span class="ruby-keyword">return</span> <span class="ruby-identifier">text</span> <span class="ruby-keyword">if</span> <span class="ruby-identifier">text</span>.<span class="ruby-identifier">size</span> <span class="ruby-operator"><=</span> <span class="ruby-identifier">max_length</span>
<span class="ruby-node">"Truncating #{description} to #{max_length.to_s.reverse.gsub(/...(?=.)/,'\&,').reverse} characters:\n"</span> <span class="ruby-operator">+</span> <span class="ruby-identifier">text</span>[<span class="ruby-value">0</span>, <span class="ruby-identifier">max_length</span>]
<span class="ruby-keyword">end</span></pre>
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