1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
|
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>class LCS::ContextDiffCallbacks - diff-lcs-1.5.0 Documentation</title>
<script type="text/javascript">
var rdoc_rel_prefix = "../";
var index_rel_prefix = "../";
</script>
<script src="../js/navigation.js" defer></script>
<script src="../js/search.js" defer></script>
<script src="../js/search_index.js" defer></script>
<script src="../js/searcher.js" defer></script>
<script src="../js/darkfish.js" defer></script>
<link href="../css/fonts.css" rel="stylesheet">
<link href="../css/rdoc.css" rel="stylesheet">
<body id="top" role="document" class="class">
<nav role="navigation">
<div id="project-navigation">
<div id="home-section" role="region" title="Quick navigation" class="nav-section">
<h2>
<a href="../index.html" rel="home">Home</a>
</h2>
<div id="table-of-contents-navigation">
<a href="../table_of_contents.html#pages">Pages</a>
<a href="../table_of_contents.html#classes">Classes</a>
<a href="../table_of_contents.html#methods">Methods</a>
</div>
</div>
<div id="search-section" role="search" class="project-section initially-hidden">
<form action="#" method="get" accept-charset="utf-8">
<div id="search-field-wrapper">
<input id="search-field" role="combobox" aria-label="Search"
aria-autocomplete="list" aria-controls="search-results"
type="text" name="search" placeholder="Search" spellcheck="false"
title="Type to search, Up and Down to navigate, Enter to load">
</div>
<ul id="search-results" aria-label="Search Results"
aria-busy="false" aria-expanded="false"
aria-atomic="false" class="initially-hidden"></ul>
</form>
</div>
</div>
<div class="nav-section">
<h3>Table of Contents</h3>
<ul class="link-list" role="directory">
<li><a href="#class-LCS::ContextDiffCallbacks-label-Use">Use</a>
<li><a href="#class-LCS::ContextDiffCallbacks-label-Simplified+Array+Format">Simplified Array Format</a>
</ul>
</div>
<div id="class-metadata">
<div id="parent-class-section" class="nav-section">
<h3>Parent</h3>
<p class="link">Diff::LCS::DiffCallbacks
</div>
<!-- Method Quickref -->
<div id="method-list-section" class="nav-section">
<h3>Methods</h3>
<ul class="link-list" role="directory">
<li ><a href="#method-i-change">#change</a>
<li ><a href="#method-i-discard_a">#discard_a</a>
<li ><a href="#method-i-discard_b">#discard_b</a>
</ul>
</div>
</div>
</nav>
<main role="main" aria-labelledby="class-LCS::ContextDiffCallbacks">
<h1 id="class-LCS::ContextDiffCallbacks" class="class">
class LCS::ContextDiffCallbacks
</h1>
<section class="description">
<p>This will produce a compound array of contextual diff change objects. Each element in the diffs array is a “hunk” array, where each element in each “hunk” array is a single change. Each change is a Diff::LCS::ContextChange that contains both the old index and new index values for the change. The “hunk” provides the full context for the changes. Both old and new objects will be presented for changed objects. <code>nil</code> will be substituted for a discarded object.</p>
<pre class="ruby"><span class="ruby-identifier">seq1</span> = <span class="ruby-node">%w(a b c e h j l m n p)</span>
<span class="ruby-identifier">seq2</span> = <span class="ruby-node">%w(b c d e f j k l m r s t)</span>
<span class="ruby-identifier">diffs</span> = <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span>.<span class="ruby-identifier">diff</span>(<span class="ruby-identifier">seq1</span>, <span class="ruby-identifier">seq2</span>, <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span><span class="ruby-operator">::</span><span class="ruby-constant">ContextDiffCallbacks</span>)
<span class="ruby-comment"># This example shows a simplified array format.</span>
<span class="ruby-comment"># [ [ [ '-', [ 0, 'a' ], [ 0, nil ] ] ], # 1</span>
<span class="ruby-comment"># [ [ '+', [ 3, nil ], [ 2, 'd' ] ] ], # 2</span>
<span class="ruby-comment"># [ [ '-', [ 4, 'h' ], [ 4, nil ] ], # 3</span>
<span class="ruby-comment"># [ '+', [ 5, nil ], [ 4, 'f' ] ] ],</span>
<span class="ruby-comment"># [ [ '+', [ 6, nil ], [ 6, 'k' ] ] ], # 4</span>
<span class="ruby-comment"># [ [ '-', [ 8, 'n' ], [ 9, nil ] ], # 5</span>
<span class="ruby-comment"># [ '+', [ 9, nil ], [ 9, 'r' ] ],</span>
<span class="ruby-comment"># [ '-', [ 9, 'p' ], [ 10, nil ] ],</span>
<span class="ruby-comment"># [ '+', [ 10, nil ], [ 10, 's' ] ],</span>
<span class="ruby-comment"># [ '+', [ 10, nil ], [ 11, 't' ] ] ] ]</span>
</pre>
<p>The five hunks shown are comprised of individual changes; if there is a related set of changes, they are still shown individually.</p>
<p>This callback can also be used with <a href="../LCS.html#method-i-sdiff"><code>Diff::LCS#sdiff</code></a>, which will produce results like:</p>
<pre class="ruby"><span class="ruby-identifier">diffs</span> = <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span>.<span class="ruby-identifier">sdiff</span>(<span class="ruby-identifier">seq1</span>, <span class="ruby-identifier">seq2</span>, <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span><span class="ruby-operator">::</span><span class="ruby-constant">ContextCallbacks</span>)
<span class="ruby-comment"># This example shows a simplified array format.</span>
<span class="ruby-comment"># [ [ [ "-", [ 0, "a" ], [ 0, nil ] ] ], # 1</span>
<span class="ruby-comment"># [ [ "+", [ 3, nil ], [ 2, "d" ] ] ], # 2</span>
<span class="ruby-comment"># [ [ "!", [ 4, "h" ], [ 4, "f" ] ] ], # 3</span>
<span class="ruby-comment"># [ [ "+", [ 6, nil ], [ 6, "k" ] ] ], # 4</span>
<span class="ruby-comment"># [ [ "!", [ 8, "n" ], [ 9, "r" ] ], # 5</span>
<span class="ruby-comment"># [ "!", [ 9, "p" ], [ 10, "s" ] ],</span>
<span class="ruby-comment"># [ "+", [ 10, nil ], [ 11, "t" ] ] ] ]</span>
</pre>
<p>The five hunks are still present, but are significantly shorter in total presentation, because changed items are shown as changes (“!”) instead of potentially “mismatched” pairs of additions and deletions.</p>
<p>The result of this operation is similar to that of Diff::LCS::SDiffCallbacks. They may be compared as:</p>
<pre class="ruby"><span class="ruby-identifier">s</span> = <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span>.<span class="ruby-identifier">sdiff</span>(<span class="ruby-identifier">seq1</span>, <span class="ruby-identifier">seq2</span>).<span class="ruby-identifier">reject</span> { <span class="ruby-operator">|</span><span class="ruby-identifier">e</span><span class="ruby-operator">|</span> <span class="ruby-identifier">e</span>.<span class="ruby-identifier">action</span> <span class="ruby-operator">==</span> <span class="ruby-string">"="</span> }
<span class="ruby-identifier">c</span> = <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span>.<span class="ruby-identifier">sdiff</span>(<span class="ruby-identifier">seq1</span>, <span class="ruby-identifier">seq2</span>, <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span><span class="ruby-operator">::</span><span class="ruby-constant">ContextDiffCallbacks</span>).<span class="ruby-identifier">flatten</span>(<span class="ruby-value">1</span>)
<span class="ruby-identifier">s</span> <span class="ruby-operator">==</span> <span class="ruby-identifier">c</span> <span class="ruby-comment"># -> true</span>
</pre>
<h3 id="class-LCS::ContextDiffCallbacks-label-Use">Use<span><a href="#class-LCS::ContextDiffCallbacks-label-Use">¶</a> <a href="#top">↑</a></span></h3>
<p>This callback object must be initialised and can be used by the <a href="../LCS.html#method-i-diff"><code>Diff::LCS#diff</code></a> or <a href="../LCS.html#method-i-sdiff"><code>Diff::LCS#sdiff</code></a> methods.</p>
<pre class="ruby"><span class="ruby-identifier">cbo</span> = <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span><span class="ruby-operator">::</span><span class="ruby-constant">ContextDiffCallbacks</span>.<span class="ruby-identifier">new</span>
<span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span>.<span class="ruby-constant">LCS</span>(<span class="ruby-identifier">seq1</span>, <span class="ruby-identifier">seq2</span>, <span class="ruby-identifier">cbo</span>)
<span class="ruby-identifier">cbo</span>.<span class="ruby-identifier">finish</span>
</pre>
<p>Note that the call to finish is absolutely necessary, or the last set of changes will not be visible. Alternatively, can be used as:</p>
<pre class="ruby"><span class="ruby-identifier">cbo</span> = <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span><span class="ruby-operator">::</span><span class="ruby-constant">ContextDiffCallbacks</span>.<span class="ruby-identifier">new</span> { <span class="ruby-operator">|</span><span class="ruby-identifier">tcbo</span><span class="ruby-operator">|</span> <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span>.<span class="ruby-constant">LCS</span>(<span class="ruby-identifier">seq1</span>, <span class="ruby-identifier">seq2</span>, <span class="ruby-identifier">tcbo</span>) }
</pre>
<p>The necessary finish call will be made.</p>
<h3 id="class-LCS::ContextDiffCallbacks-label-Simplified+Array+Format">Simplified <a href="../Array.html"><code>Array</code></a> Format<span><a href="#class-LCS::ContextDiffCallbacks-label-Simplified+Array+Format">¶</a> <a href="#top">↑</a></span></h3>
<p>The simplified array format used in the example above can be obtained with:</p>
<pre class="ruby"><span class="ruby-identifier">require</span> <span class="ruby-string">'pp'</span>
<span class="ruby-identifier">pp</span> <span class="ruby-identifier">diffs</span>.<span class="ruby-identifier">map</span> { <span class="ruby-operator">|</span><span class="ruby-identifier">e</span><span class="ruby-operator">|</span> <span class="ruby-identifier">e</span>.<span class="ruby-identifier">map</span> { <span class="ruby-operator">|</span><span class="ruby-identifier">f</span><span class="ruby-operator">|</span> <span class="ruby-identifier">f</span>.<span class="ruby-identifier">to_a</span> } }
</pre>
</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-change" class="method-detail ">
<div class="method-heading">
<span class="method-name">change</span><span
class="method-args">(event)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<div class="method-source-code" id="change-source">
<pre><span class="ruby-comment"># File lib/diff/lcs/callbacks.rb, line 232</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">change</span>(<span class="ruby-identifier">event</span>)
<span class="ruby-ivar">@hunk</span> <span class="ruby-operator"><<</span> <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span><span class="ruby-operator">::</span><span class="ruby-constant">ContextChange</span>.<span class="ruby-identifier">simplify</span>(<span class="ruby-identifier">event</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-discard_a" class="method-detail ">
<div class="method-heading">
<span class="method-name">discard_a</span><span
class="method-args">(event)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<div class="method-source-code" id="discard_a-source">
<pre><span class="ruby-comment"># File lib/diff/lcs/callbacks.rb, line 224</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">discard_a</span>(<span class="ruby-identifier">event</span>)
<span class="ruby-ivar">@hunk</span> <span class="ruby-operator"><<</span> <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span><span class="ruby-operator">::</span><span class="ruby-constant">ContextChange</span>.<span class="ruby-identifier">simplify</span>(<span class="ruby-identifier">event</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
<div id="method-i-discard_b" class="method-detail ">
<div class="method-heading">
<span class="method-name">discard_b</span><span
class="method-args">(event)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<div class="method-source-code" id="discard_b-source">
<pre><span class="ruby-comment"># File lib/diff/lcs/callbacks.rb, line 228</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">discard_b</span>(<span class="ruby-identifier">event</span>)
<span class="ruby-ivar">@hunk</span> <span class="ruby-operator"><<</span> <span class="ruby-constant">Diff</span><span class="ruby-operator">::</span><span class="ruby-constant">LCS</span><span class="ruby-operator">::</span><span class="ruby-constant">ContextChange</span>.<span class="ruby-identifier">simplify</span>(<span class="ruby-identifier">event</span>)
<span class="ruby-keyword">end</span></pre>
</div>
</div>
</div>
</section>
</section>
</main>
<footer id="validator-badges" role="contentinfo">
<p><a href="https://validator.w3.org/check/referer">Validate</a>
<p>Generated by <a href="https://ruby.github.io/rdoc/">RDoc</a> 6.3.3.
<p>Based on <a href="http://deveiate.org/projects/Darkfish-RDoc/">Darkfish</a> by <a href="http://deveiate.org">Michael Granger</a>.
</footer>
|
