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diff --git a/share/doc/gdb/Parameters-In-Guile.html b/share/doc/gdb/Parameters-In-Guile.html new file mode 100644 index 0000000..55613f9 --- /dev/null +++ b/share/doc/gdb/Parameters-In-Guile.html @@ -0,0 +1,296 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Free Software" and "Free Software Needs +Free Documentation", with the Front-Cover Texts being "A GNU Manual," +and with the Back-Cover Texts as in (a) below. + +(a) The FSF's Back-Cover Text is: "You are free to copy and modify +this GNU Manual. Buying copies from GNU Press supports the FSF in +developing GNU and promoting software freedom." --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>Debugging with GDB: Parameters In Guile</title> + +<meta name="description" content="Debugging with GDB: Parameters In Guile"> +<meta name="keywords" content="Debugging with GDB: Parameters In Guile"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Concept-Index.html#Concept-Index" rel="index" title="Concept Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Guile-API.html#Guile-API" rel="up" title="Guile API"> +<link href="Progspaces-In-Guile.html#Progspaces-In-Guile" rel="next" title="Progspaces In Guile"> +<link href="Commands-In-Guile.html#Commands-In-Guile" rel="previous" title="Commands In Guile"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {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} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="Parameters-In-Guile"></a> +<div class="header"> +<p> +Next: <a href="Progspaces-In-Guile.html#Progspaces-In-Guile" accesskey="n" rel="next">Progspaces In Guile</a>, Previous: <a href="Commands-In-Guile.html#Commands-In-Guile" accesskey="p" rel="previous">Commands In Guile</a>, Up: <a href="Guile-API.html#Guile-API" accesskey="u" rel="up">Guile API</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Parameters-In-Guile-1"></a> +<h4 class="subsubsection">23.4.3.12 Parameters In Guile</h4> + +<a name="index-parameters-in-guile"></a> +<a name="index-guile-parameters"></a> +<a name="index-Parameter-1"></a> +<p>You can implement new <small>GDB</small> <em>parameters</em> using Guile +<a name="DOCF20" href="#FOOT20"><sup>20</sup></a>. +</p> +<p>There are many parameters that already exist and can be set in +<small>GDB</small>. Two examples are: <code>set follow-fork</code> and +<code>set charset</code>. Setting these parameters influences certain +behavior in <small>GDB</small>. Similarly, you can define parameters that +can be used to influence behavior in custom Guile scripts and commands. +</p> +<p>A new parameter is defined with the <code>make-parameter</code> Guile function, +and added to <small>GDB</small> with the <code>register-parameter!</code> Guile function. +This two-step approach is taken to separate out the side-effect of adding +the parameter to <small>GDB</small> from <code>make-parameter</code>. +</p> +<p>Parameters are exposed to the user via the <code>set</code> and +<code>show</code> commands. See <a href="Help.html#Help">Help</a>. +</p> +<dl> +<dt><a name="index-make_002dparameter"></a>Scheme Procedure: <strong>make-parameter</strong> <em>name <span class="roman">[</span><span class="nolinebreak">#:command-class</span> <span class="nolinebreak">command-class</span><span class="roman">]</span><!-- /@w --> <span class="roman">[</span><span class="nolinebreak">#:parameter-type</span> <span class="nolinebreak">parameter-type</span><span class="roman">]</span><!-- /@w --> <span class="roman">[</span><span class="nolinebreak">#:enum-list</span> <span class="nolinebreak">enum-list</span><span class="roman">]</span><!-- /@w --> <span class="roman">[</span><span class="nolinebreak">#:set-func</span> <span class="nolinebreak">set-func</span><span class="roman">]</span><!-- /@w --> <span class="roman">[</span><span class="nolinebreak">#:show-func</span> <span class="nolinebreak">show-func</span><span class="roman">]</span><!-- /@w --> <span class="roman">[</span>#:doc doc<span class="roman">]</span><!-- /@w --> <span class="roman">[</span><span class="nolinebreak">#:set-doc</span> <span class="nolinebreak">set-doc</span><span class="roman">]</span><!-- /@w --> <span class="roman">[</span><span class="nolinebreak">#:show-doc</span> <span class="nolinebreak">show-doc</span><span class="roman">]</span><!-- /@w --> <span class="roman">[</span><span class="nolinebreak">#:initial-value</span> <span class="nolinebreak">initial-value</span><span class="roman">]</span><!-- /@w --></em></dt> +<dd> +<p>The argument <var>name</var> is the name of the new parameter. If <var>name</var> +consists of multiple words, then the initial words are looked for as prefix +parameters. An example of this can be illustrated with the +<code>set print</code> set of parameters. If <var>name</var> is +<code>print foo</code>, then <code>print</code> will be searched as the prefix +parameter. In this case the parameter can subsequently be accessed in +<small>GDB</small> as <code>set print foo</code>. +If <var>name</var> consists of multiple words, and no prefix parameter group +can be found, an exception is raised. +</p> +<p>The result is the <code><gdb:parameter></code> object representing the parameter. +The parameter is not usable until it has been registered with <small>GDB</small> +with <code>register-parameter!</code>. +</p> +<p>The rest of the arguments are optional. +</p> +<p>The argument <var>command-class</var> should be one of the ‘<samp>COMMAND_</samp>’ constants +(see <a href="Commands-In-Guile.html#Commands-In-Guile">Commands In Guile</a>). This argument tells <small>GDB</small> how to +categorize the new parameter in the help system. +The default is <code>COMMAND_NONE</code>. +</p> +<p>The argument <var>parameter-type</var> should be one of the ‘<samp>PARAM_</samp>’ constants +defined below. This argument tells <small>GDB</small> the type of the new +parameter; this information is used for input validation and +completion. The default is <code>PARAM_BOOLEAN</code>. +</p> +<p>If <var>parameter-type</var> is <code>PARAM_ENUM</code>, then +<var>enum-list</var> must be a list of strings. These strings +represent the possible values for the parameter. +</p> +<p>If <var>parameter-type</var> is not <code>PARAM_ENUM</code>, then the presence +of <var>enum-list</var> will cause an exception to be thrown. +</p> +<p>The argument <var>set-func</var> is a function of one argument: <var>self</var> which +is the <code><gdb:parameter></code> object representing the parameter. +<small>GDB</small> will call this function when a <var>parameter</var>’s value has +been changed via the <code>set</code> API (for example, <kbd>set foo off</kbd>). +The value of the parameter has already been set to the new value. +This function must return a string to be displayed to the user. +<small>GDB</small> will add a trailing newline if the string is non-empty. +<small>GDB</small> generally doesn’t print anything when a parameter is set, +thus typically this function should return ‘<samp>""</samp>’. +A non-empty string result should typically be used for displaying warnings +and errors. +</p> +<p>The argument <var>show-func</var> is a function of two arguments: <var>self</var> which +is the <code><gdb:parameter></code> object representing the parameter, and +<var>svalue</var> which is the string representation of the current value. +<small>GDB</small> will call this function when a <var>parameter</var>’s +<code>show</code> API has been invoked (for example, <kbd>show foo</kbd>). +This function must return a string, and will be displayed to the user. +<small>GDB</small> will add a trailing newline. +</p> +<p>The argument <var>doc</var> is the help text for the new parameter. +If there is no documentation string, a default value is used. +</p> +<p>The argument <var>set-doc</var> is the help text for this parameter’s +<code>set</code> command. +</p> +<p>The argument <var>show-doc</var> is the help text for this parameter’s +<code>show</code> command. +</p> +<p>The argument <var>initial-value</var> specifies the initial value of the parameter. +If it is a function, it takes one parameter, the <code><gdb:parameter></code> +object and its result is used as the initial value of the parameter. +The initial value must be valid for the parameter type, +otherwise an exception is thrown. +</p></dd></dl> + +<dl> +<dt><a name="index-register_002dparameter_0021"></a>Scheme Procedure: <strong>register-parameter!</strong> <em>parameter</em></dt> +<dd><p>Add <var>parameter</var>, a <code><gdb:parameter></code> object, to <small>GDB</small>’s +list of parameters. +It is an error to register a parameter more than once. +The result is unspecified. +</p></dd></dl> + +<dl> +<dt><a name="index-parameter_003f"></a>Scheme Procedure: <strong>parameter?</strong> <em>object</em></dt> +<dd><p>Return <code>#t</code> if <var>object</var> is a <code><gdb:parameter></code> object. +Otherwise return <code>#f</code>. +</p></dd></dl> + +<dl> +<dt><a name="index-parameter_002dvalue"></a>Scheme Procedure: <strong>parameter-value</strong> <em>parameter</em></dt> +<dd><p>Return the value of <var>parameter</var> which may either be +a <code><gdb:parameter></code> object or a string naming the parameter. +</p></dd></dl> + +<dl> +<dt><a name="index-set_002dparameter_002dvalue_0021"></a>Scheme Procedure: <strong>set-parameter-value!</strong> <em>parameter new-value</em></dt> +<dd><p>Assign <var>parameter</var> the value of <var>new-value</var>. +The argument <var>parameter</var> must be an object of type <code><gdb:parameter></code>. +<small>GDB</small> does validation when assignments are made. +</p></dd></dl> + +<p>When a new parameter is defined, its type must be specified. The +available types are represented by constants defined in the <code>gdb</code> +module: +</p> +<dl compact="compact"> +<dt><code>PARAM_BOOLEAN</code> +<a name="index-PARAM_005fBOOLEAN-1"></a> +</dt> +<dd><p>The value is a plain boolean. The Guile boolean values, <code>#t</code> +and <code>#f</code> are the only valid values. +</p> +</dd> +<dt><code>PARAM_AUTO_BOOLEAN</code> +<a name="index-PARAM_005fAUTO_005fBOOLEAN-1"></a> +</dt> +<dd><p>The value has three possible states: true, false, and ‘<samp>auto</samp>’. In +Guile, true and false are represented using boolean constants, and +‘<samp>auto</samp>’ is represented using <code>#:auto</code>. +</p> +</dd> +<dt><code>PARAM_UINTEGER</code> +<a name="index-PARAM_005fUINTEGER-1"></a> +</dt> +<dd><p>The value is an unsigned integer. The value of <code>#:unlimited</code> +should be interpreted to mean “unlimited”, and the value of ‘<samp>0</samp>’ +is reserved and should not be used. +</p> +</dd> +<dt><code>PARAM_ZINTEGER</code> +<a name="index-PARAM_005fZINTEGER-1"></a> +</dt> +<dd><p>The value is an integer. +</p> +</dd> +<dt><code>PARAM_ZUINTEGER</code> +<a name="index-PARAM_005fZUINTEGER-1"></a> +</dt> +<dd><p>The value is an unsigned integer. +</p> +</dd> +<dt><code>PARAM_ZUINTEGER_UNLIMITED</code> +<a name="index-PARAM_005fZUINTEGER_005fUNLIMITED-1"></a> +</dt> +<dd><p>The value is an integer in the range ‘<samp>[0, INT_MAX]</samp>’. The value +of <code>#:unlimited</code> means “unlimited”, the value of ‘<samp>-1</samp>’ is +reserved and should not be used, and other negative numbers are not +allowed. +</p> +</dd> +<dt><code>PARAM_STRING</code> +<a name="index-PARAM_005fSTRING-1"></a> +</dt> +<dd><p>The value is a string. When the user modifies the string, any escape +sequences, such as ‘<samp>\t</samp>’, ‘<samp>\f</samp>’, and octal escapes, are +translated into corresponding characters and encoded into the current +host charset. +</p> +</dd> +<dt><code>PARAM_STRING_NOESCAPE</code> +<a name="index-PARAM_005fSTRING_005fNOESCAPE-1"></a> +</dt> +<dd><p>The value is a string. When the user modifies the string, escapes are +passed through untranslated. +</p> +</dd> +<dt><code>PARAM_OPTIONAL_FILENAME</code> +<a name="index-PARAM_005fOPTIONAL_005fFILENAME-1"></a> +</dt> +<dd><p>The value is a either a filename (a string), or <code>#f</code>. +</p> +</dd> +<dt><code>PARAM_FILENAME</code> +<a name="index-PARAM_005fFILENAME-1"></a> +</dt> +<dd><p>The value is a filename. This is just like +<code>PARAM_STRING_NOESCAPE</code>, but uses file names for completion. +</p> +</dd> +<dt><code>PARAM_ENUM</code> +<a name="index-PARAM_005fENUM-1"></a> +</dt> +<dd><p>The value is a string, which must be one of a collection of string +constants provided when the parameter is created. +</p></dd> +</dl> + +<div class="footnote"> +<hr> +<h4 class="footnotes-heading">Footnotes</h4> + +<h3><a name="FOOT20" href="#DOCF20">(20)</a></h3> +<p>Note that <small>GDB</small> parameters must not be confused with +Guileâs parameter objects (see <a href="http://www.gnu.org/software/guile/manual/html_node/Parameters.html#Parameters">Parameters</a> in <cite>GNU Guile +Reference Manual</cite>).</p> +</div> +<hr> +<div class="header"> +<p> +Next: <a href="Progspaces-In-Guile.html#Progspaces-In-Guile" accesskey="n" rel="next">Progspaces In Guile</a>, Previous: <a href="Commands-In-Guile.html#Commands-In-Guile" accesskey="p" rel="previous">Commands In Guile</a>, Up: <a href="Guile-API.html#Guile-API" accesskey="u" rel="up">Guile API</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |