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
|
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- Created by GNU Texinfo 6.7, http://www.gnu.org/software/texinfo/ -->
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Parser (GNU Octave (version 6.2.0))</title>
<meta name="description" content="Parser (GNU Octave (version 6.2.0))">
<meta name="keywords" content="Parser (GNU Octave (version 6.2.0))">
<meta name="resource-type" content="document">
<meta name="distribution" content="global">
<meta name="Generator" content="makeinfo">
<link href="index.html" rel="start" title="Top">
<link href="Concept-Index.html" rel="index" title="Concept Index">
<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
<link href="Grammar-and-Parser.html" rel="up" title="Grammar and Parser">
<link href="Copying.html" rel="next" title="Copying">
<link href="Keywords.html" rel="prev" title="Keywords">
<style type="text/css">
<!--
a.summary-letter {text-decoration: none}
blockquote.indentedblock {margin-right: 0em}
div.display {margin-left: 3.2em}
div.example {margin-left: 3.2em}
div.lisp {margin-left: 3.2em}
kbd {font-style: oblique}
pre.display {font-family: inherit}
pre.format {font-family: inherit}
pre.menu-comment {font-family: serif}
pre.menu-preformatted {font-family: serif}
span.nolinebreak {white-space: nowrap}
span.roman {font-family: initial; font-weight: normal}
span.sansserif {font-family: sans-serif; font-weight: normal}
ul.no-bullet {list-style: none}
-->
</style>
<link rel="stylesheet" type="text/css" href="octave.css">
</head>
<body lang="en">
<span id="Parser"></span><div class="header">
<p>
Previous: <a href="Keywords.html" accesskey="p" rel="prev">Keywords</a>, Up: <a href="Grammar-and-Parser.html" accesskey="u" rel="up">Grammar and Parser</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html" title="Index" rel="index">Index</a>]</p>
</div>
<hr>
<span id="Parser-1"></span><h3 class="section">F.2 Parser</h3>
<span id="index-parser"></span>
<p>The parser has a number of variables that affect its internal operation.
These variables are generally documented in the manual alongside the code that
they affect.
</p>
<p>In addition, there are three non-specific parser customization functions.
<code>add_input_event_hook</code> can be used to schedule a user function for
periodic evaluation. <code>remove_input_event_hook</code> will stop a user function
from being evaluated periodically.
</p>
<span id="XREFadd_005finput_005fevent_005fhook"></span><dl>
<dt id="index-add_005finput_005fevent_005fhook">: <em><var>id</var> =</em> <strong>add_input_event_hook</strong> <em>(<var>fcn</var>)</em></dt>
<dt id="index-add_005finput_005fevent_005fhook-1">: <em><var>id</var> =</em> <strong>add_input_event_hook</strong> <em>(<var>fcn</var>, <var>data</var>)</em></dt>
<dd><p>Add the named function or function handle <var>fcn</var> to the list of functions
to call periodically when Octave is waiting for input.
</p>
<p>The function should have the form
</p>
<div class="example">
<pre class="example"><var>fcn</var> (<var>data</var>)
</pre></div>
<p>If <var>data</var> is omitted, Octave calls the function without any arguments.
</p>
<p>The returned identifier may be used to remove the function handle from the
list of input hook functions.
</p>
<p><strong>See also:</strong> <a href="#XREFremove_005finput_005fevent_005fhook">remove_input_event_hook</a>.
</p></dd></dl>
<span id="XREFremove_005finput_005fevent_005fhook"></span><dl>
<dt id="index-remove_005finput_005fevent_005fhook">: <em></em> <strong>remove_input_event_hook</strong> <em>(<var>name</var>)</em></dt>
<dt id="index-remove_005finput_005fevent_005fhook-1">: <em></em> <strong>remove_input_event_hook</strong> <em>(<var>fcn_id</var>)</em></dt>
<dd><p>Remove the named function or function handle with the given identifier
from the list of functions to call periodically when Octave is waiting
for input.
</p>
<p><strong>See also:</strong> <a href="#XREFadd_005finput_005fevent_005fhook">add_input_event_hook</a>.
</p></dd></dl>
<p>Finally, when the parser cannot identify an input token it calls a particular
function to handle this. By default, this is the internal function
<code>"__unimplemented__"</code> which makes suggestions about possible Octave
substitutes for <small>MATLAB</small> functions.
</p>
<span id="XREFmissing_005ffunction_005fhook"></span><dl>
<dt id="index-missing_005ffunction_005fhook">: <em><var>val</var> =</em> <strong>missing_function_hook</strong> <em>()</em></dt>
<dt id="index-missing_005ffunction_005fhook-1">: <em><var>old_val</var> =</em> <strong>missing_function_hook</strong> <em>(<var>new_val</var>)</em></dt>
<dt id="index-missing_005ffunction_005fhook-2">: <em></em> <strong>missing_function_hook</strong> <em>(<var>new_val</var>, "local")</em></dt>
<dd><p>Query or set the internal variable that specifies the function to call
to provide extra information when an unknown identifier is referenced.
</p>
<p>When called from inside a function with the <code>"local"</code> option, the
variable is changed locally for the function and any subroutines it calls.
The original variable value is restored when exiting the function.
</p>
<p><strong>See also:</strong> <a href="Missing-Components.html#XREFmissing_005fcomponent_005fhook">missing_component_hook</a>.
</p></dd></dl>
<hr>
<div class="header">
<p>
Previous: <a href="Keywords.html" accesskey="p" rel="prev">Keywords</a>, Up: <a href="Grammar-and-Parser.html" accesskey="u" rel="up">Grammar and Parser</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html" title="Index" rel="index">Index</a>]</p>
</div>
</body>
</html>
|
