File: filterdevelopment.html

package info (click to toggle)
pygments 1.3.1%2Bdfsg-1
  • links: PTS, VCS
  • area: main
  • in suites: squeeze
  • size: 2,648 kB
  • ctags: 2,184
  • sloc: python: 20,142; makefile: 84; sh: 30
file content (282 lines) | stat: -rw-r--r-- 12,664 bytes parent folder | download | duplicates (2)
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
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
   "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
  <title>Write your own filter &mdash; Pygments</title>
  <meta http-equiv="content-type" content="text/html; charset=utf-8">
  <style type="text/css">
    body {
    background-color: #f2f2f2;
    margin: 0;
    padding: 0;
    font-family: 'Georgia', serif;
    color: #111;
}

#content {
    background-color: white;
    padding: 20px;
    margin: 20px auto 20px auto;
    max-width: 800px;
    border: 4px solid #ddd;
}

h1 {
    font-weight: normal;
    font-size: 40px;
    color: #09839A;
}

h2 {
    font-weight: normal;
    font-size: 30px;
    color: #C73F00;
}

h1.heading {
    margin: 0 0 30px 0;
}

h2.subheading {
    margin: -30px 0 0 45px;
}

h3 {
    margin-top: 30px;
}

table.docutils {
    border-collapse: collapse;
    border: 2px solid #aaa;
    margin: 0.5em 1.5em 0.5em 1.5em;
}

table.docutils td {
    padding: 2px;
    border: 1px solid #ddd;
}

p, li, dd, dt, blockquote {
    font-size: 15px;
    color: #333;
}

p {
    line-height: 150%;
    margin-bottom: 0;
    margin-top: 10px;
}

hr {
    border-top: 1px solid #ccc;
    border-bottom: 0;
    border-right: 0;
    border-left: 0;
    margin-bottom: 10px;
    margin-top: 20px;
}

dl {
    margin-left: 10px;
}

li, dt {
    margin-top: 5px;
}

dt {
    font-weight: bold;
}

th {
    text-align: left;
}

a {
    color: #990000;
}

a:hover {
    color: #c73f00;
}

pre {
    background-color: #f9f9f9;
    border-top: 1px solid #ccc;
    border-bottom: 1px solid #ccc;
    padding: 5px;
    font-size: 13px;
    font-family: Bitstream Vera Sans Mono,monospace;
}

tt {
    font-size: 13px;
    font-family: Bitstream Vera Sans Mono,monospace;
    color: black;
    padding: 1px 2px 1px 2px;
    background-color: #f0f0f0;
}

cite {
    /* abusing <cite>, it's generated by ReST for `x` */
    font-size: 13px;
    font-family: Bitstream Vera Sans Mono,monospace;
    font-weight: bold;
    font-style: normal;
}

#backlink {
    float: right;
    font-size: 11px;
    color: #888;
}

div.toc {
    margin: 0 0 10px 0;
}

div.toc h2 {
    font-size: 20px;
}
.syntax .hll { background-color: #ffffcc }
.syntax  { background: #ffffff; }
.syntax .c { color: #888888 } /* Comment */
.syntax .err { color: #a61717; background-color: #e3d2d2 } /* Error */
.syntax .k { color: #008800; font-weight: bold } /* Keyword */
.syntax .cm { color: #888888 } /* Comment.Multiline */
.syntax .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */
.syntax .c1 { color: #888888 } /* Comment.Single */
.syntax .cs { color: #cc0000; font-weight: bold; background-color: #fff0f0 } /* Comment.Special */
.syntax .gd { color: #000000; background-color: #ffdddd } /* Generic.Deleted */
.syntax .ge { font-style: italic } /* Generic.Emph */
.syntax .gr { color: #aa0000 } /* Generic.Error */
.syntax .gh { color: #303030 } /* Generic.Heading */
.syntax .gi { color: #000000; background-color: #ddffdd } /* Generic.Inserted */
.syntax .go { color: #888888 } /* Generic.Output */
.syntax .gp { color: #555555 } /* Generic.Prompt */
.syntax .gs { font-weight: bold } /* Generic.Strong */
.syntax .gu { color: #606060 } /* Generic.Subheading */
.syntax .gt { color: #aa0000 } /* Generic.Traceback */
.syntax .kc { color: #008800; font-weight: bold } /* Keyword.Constant */
.syntax .kd { color: #008800; font-weight: bold } /* Keyword.Declaration */
.syntax .kn { color: #008800; font-weight: bold } /* Keyword.Namespace */
.syntax .kp { color: #008800 } /* Keyword.Pseudo */
.syntax .kr { color: #008800; font-weight: bold } /* Keyword.Reserved */
.syntax .kt { color: #888888; font-weight: bold } /* Keyword.Type */
.syntax .m { color: #0000DD; font-weight: bold } /* Literal.Number */
.syntax .s { color: #dd2200; background-color: #fff0f0 } /* Literal.String */
.syntax .na { color: #336699 } /* Name.Attribute */
.syntax .nb { color: #003388 } /* Name.Builtin */
.syntax .nc { color: #bb0066; font-weight: bold } /* Name.Class */
.syntax .no { color: #003366; font-weight: bold } /* Name.Constant */
.syntax .nd { color: #555555 } /* Name.Decorator */
.syntax .ne { color: #bb0066; font-weight: bold } /* Name.Exception */
.syntax .nf { color: #0066bb; font-weight: bold } /* Name.Function */
.syntax .nl { color: #336699; font-style: italic } /* Name.Label */
.syntax .nn { color: #bb0066; font-weight: bold } /* Name.Namespace */
.syntax .py { color: #336699; font-weight: bold } /* Name.Property */
.syntax .nt { color: #bb0066; font-weight: bold } /* Name.Tag */
.syntax .nv { color: #336699 } /* Name.Variable */
.syntax .ow { color: #008800 } /* Operator.Word */
.syntax .w { color: #bbbbbb } /* Text.Whitespace */
.syntax .mf { color: #0000DD; font-weight: bold } /* Literal.Number.Float */
.syntax .mh { color: #0000DD; font-weight: bold } /* Literal.Number.Hex */
.syntax .mi { color: #0000DD; font-weight: bold } /* Literal.Number.Integer */
.syntax .mo { color: #0000DD; font-weight: bold } /* Literal.Number.Oct */
.syntax .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */
.syntax .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */
.syntax .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */
.syntax .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */
.syntax .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */
.syntax .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */
.syntax .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */
.syntax .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */
.syntax .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */
.syntax .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */
.syntax .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */
.syntax .bp { color: #003388 } /* Name.Builtin.Pseudo */
.syntax .vc { color: #336699 } /* Name.Variable.Class */
.syntax .vg { color: #dd7700 } /* Name.Variable.Global */
.syntax .vi { color: #3333bb } /* Name.Variable.Instance */
.syntax .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */
  </style>
</head>
<body>
  <div id="content">
    <h1 class="heading">Pygments</h1>
    <h2 class="subheading">Write your own filter</h2>
    
      <a id="backlink" href="index.html">&laquo; Back To Index</a>
    
    
      <div class="toc">
        <h2>Contents</h2>
        <ul class="contents">
        
          <li><a href="#subclassing-filters">Subclassing Filters</a></li>
        
          <li><a href="#using-a-decorator">Using a decorator</a></li>
        
        </ul>
      </div>
    
    <!-- -*- mode: rst -*- -->
<p><em>New in Pygments 0.7.</em></p>
<p>Writing own filters is very easy. All you have to do is to subclass
the <cite>Filter</cite> class and override the <cite>filter</cite> method. Additionally a
filter is instanciated with some keyword arguments you can use to
adjust the behavior of your filter.</p>
<div class="section" id="subclassing-filters">
<h3>Subclassing Filters</h3>
<p>As an example, we write a filter that converts all <cite>Name.Function</cite> tokens
to normal <cite>Name</cite> tokens to make the output less colorful.</p>
<div class="syntax"><pre><span class="kn">from</span> <span class="nn">pygments.util</span> <span class="kn">import</span> <span class="n">get_bool_opt</span>
<span class="kn">from</span> <span class="nn">pygments.token</span> <span class="kn">import</span> <span class="n">Name</span>
<span class="kn">from</span> <span class="nn">pygments.filter</span> <span class="kn">import</span> <span class="n">Filter</span>

<span class="k">class</span> <span class="nc">UncolorFilter</span><span class="p">(</span><span class="n">Filter</span><span class="p">):</span>

    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">**</span><span class="n">options</span><span class="p">):</span>
        <span class="n">Filter</span><span class="o">.</span><span class="n">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">**</span><span class="n">options</span><span class="p">)</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">class_too</span> <span class="o">=</span> <span class="n">get_bool_opt</span><span class="p">(</span><span class="n">options</span><span class="p">,</span> <span class="s">&#39;classtoo&#39;</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">filter</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">lexer</span><span class="p">,</span> <span class="n">stream</span><span class="p">):</span>
        <span class="k">for</span> <span class="n">ttype</span><span class="p">,</span> <span class="n">value</span> <span class="ow">in</span> <span class="n">stream</span><span class="p">:</span>
            <span class="k">if</span> <span class="n">ttype</span> <span class="ow">is</span> <span class="n">Name</span><span class="o">.</span><span class="n">Function</span> <span class="ow">or</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">class_too</span> <span class="ow">and</span>
                                          <span class="n">ttype</span> <span class="ow">is</span> <span class="n">Name</span><span class="o">.</span><span class="n">Class</span><span class="p">):</span>
                <span class="n">ttype</span> <span class="o">=</span> <span class="n">Name</span>
            <span class="k">yield</span> <span class="n">ttype</span><span class="p">,</span> <span class="n">value</span>
</pre></div>
<p>Some notes on the <cite>lexer</cite> argument: that can be quite confusing since it doesn't
need to be a lexer instance. If a filter was added by using the <cite>add_filter()</cite>
function of lexers, that lexer is registered for the filter. In that case
<cite>lexer</cite> will refer to the lexer that has registered the filter. It <em>can</em> be used
to access options passed to a lexer. Because it could be <cite>None</cite> you always have
to check for that case if you access it.</p>
</div>
<div class="section" id="using-a-decorator">
<h3>Using a decorator</h3>
<p>You can also use the <cite>simplefilter</cite> decorator from the <cite>pygments.filter</cite> module:</p>
<div class="syntax"><pre><span class="kn">from</span> <span class="nn">pygments.util</span> <span class="kn">import</span> <span class="n">get_bool_opt</span>
<span class="kn">from</span> <span class="nn">pygments.token</span> <span class="kn">import</span> <span class="n">Name</span>
<span class="kn">from</span> <span class="nn">pygments.filter</span> <span class="kn">import</span> <span class="n">simplefilter</span>


<span class="nd">@simplefilter</span>
<span class="k">def</span> <span class="nf">uncolor</span><span class="p">(</span><span class="n">lexer</span><span class="p">,</span> <span class="n">stream</span><span class="p">,</span> <span class="n">options</span><span class="p">):</span>
    <span class="n">class_too</span> <span class="o">=</span> <span class="n">get_bool_opt</span><span class="p">(</span><span class="n">options</span><span class="p">,</span> <span class="s">&#39;classtoo&#39;</span><span class="p">)</span>
    <span class="k">for</span> <span class="n">ttype</span><span class="p">,</span> <span class="n">value</span> <span class="ow">in</span> <span class="n">stream</span><span class="p">:</span>
        <span class="k">if</span> <span class="n">ttype</span> <span class="ow">is</span> <span class="n">Name</span><span class="o">.</span><span class="n">Function</span> <span class="ow">or</span> <span class="p">(</span><span class="n">class_too</span> <span class="ow">and</span>
                                      <span class="n">ttype</span> <span class="ow">is</span> <span class="n">Name</span><span class="o">.</span><span class="n">Class</span><span class="p">):</span>
            <span class="n">ttype</span> <span class="o">=</span> <span class="n">Name</span>
        <span class="k">yield</span> <span class="n">ttype</span><span class="p">,</span> <span class="n">value</span>
</pre></div>
<p>The decorator automatically subclasses an internal filter class and uses the
decorated function for filtering.</p>
</div>

  </div>
</body>
<!-- generated on: 2010-03-01 21:18:23.568890
     file id: filterdevelopment -->
</html>