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| author | alk3pInjection <webmaster@raspii.tech> | 2024-02-04 16:16:35 +0800 |
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| committer | alk3pInjection <webmaster@raspii.tech> | 2024-02-04 16:16:35 +0800 |
| commit | 6ce4ebed87858ecdd79a1091367c6e961055daa9 (patch) | |
| tree | 1c2a6a60531acf791531bbd9c8ac14c23ef8a66c /share/doc/gdb/Guile-Pretty-Printing-API.html | |
https://developer.arm.com/downloads/-/arm-gnu-toolchain-downloads
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diff --git a/share/doc/gdb/Guile-Pretty-Printing-API.html b/share/doc/gdb/Guile-Pretty-Printing-API.html new file mode 100644 index 0000000..4e60454 --- /dev/null +++ b/share/doc/gdb/Guile-Pretty-Printing-API.html @@ -0,0 +1,234 @@ +<!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: Guile Pretty Printing API</title> + +<meta name="description" content="Debugging with GDB: Guile Pretty Printing API"> +<meta name="keywords" content="Debugging with GDB: Guile Pretty Printing API"> +<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="Selecting-Guile-Pretty_002dPrinters.html#Selecting-Guile-Pretty_002dPrinters" rel="next" title="Selecting Guile Pretty-Printers"> +<link href="Types-In-Guile.html#Types-In-Guile" rel="previous" title="Types 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="Guile-Pretty-Printing-API"></a> +<div class="header"> +<p> +Next: <a href="Selecting-Guile-Pretty_002dPrinters.html#Selecting-Guile-Pretty_002dPrinters" accesskey="n" rel="next">Selecting Guile Pretty-Printers</a>, Previous: <a href="Types-In-Guile.html#Types-In-Guile" accesskey="p" rel="previous">Types 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="Guile-Pretty-Printing-API-1"></a> +<h4 class="subsubsection">23.4.3.8 Guile Pretty Printing API</h4> +<a name="index-guile-pretty-printing-api"></a> + +<p>An example output is provided (see <a href="Pretty-Printing.html#Pretty-Printing">Pretty Printing</a>). +</p> +<p>A pretty-printer is represented by an object of type <gdb:pretty-printer>. +Pretty-printer objects are created with <code>make-pretty-printer</code>. +</p> +<p>The following pretty-printer-related procedures are provided by the +<code>(gdb)</code> module: +</p> +<dl> +<dt><a name="index-make_002dpretty_002dprinter"></a>Scheme Procedure: <strong>make-pretty-printer</strong> <em>name lookup-function</em></dt> +<dd><p>Return a <code><gdb:pretty-printer></code> object named <var>name</var>. +</p> +<p><var>lookup-function</var> is a function of one parameter: the value to +be printed. If the value is handled by this pretty-printer, then +<var>lookup-function</var> returns an object of type +<gdb:pretty-printer-worker> to perform the actual pretty-printing. +Otherwise <var>lookup-function</var> returns <code>#f</code>. +</p></dd></dl> + +<dl> +<dt><a name="index-pretty_002dprinter_003f"></a>Scheme Procedure: <strong>pretty-printer?</strong> <em>object</em></dt> +<dd><p>Return <code>#t</code> if <var>object</var> is a <code><gdb:pretty-printer></code> object. +Otherwise return <code>#f</code>. +</p></dd></dl> + +<dl> +<dt><a name="index-pretty_002dprinter_002denabled_003f"></a>Scheme Procedure: <strong>pretty-printer-enabled?</strong> <em>pretty-printer</em></dt> +<dd><p>Return <code>#t</code> if <var>pretty-printer</var> is enabled. +Otherwise return <code>#f</code>. +</p></dd></dl> + +<dl> +<dt><a name="index-set_002dpretty_002dprinter_002denabled_0021"></a>Scheme Procedure: <strong>set-pretty-printer-enabled!</strong> <em>pretty-printer flag</em></dt> +<dd><p>Set the enabled flag of <var>pretty-printer</var> to <var>flag</var>. +The value returned is unspecified. +</p></dd></dl> + +<dl> +<dt><a name="index-pretty_002dprinters"></a>Scheme Procedure: <strong>pretty-printers</strong></dt> +<dd><p>Return the list of global pretty-printers. +</p></dd></dl> + +<dl> +<dt><a name="index-set_002dpretty_002dprinters_0021"></a>Scheme Procedure: <strong>set-pretty-printers!</strong> <em>pretty-printers</em></dt> +<dd><p>Set the list of global pretty-printers to <var>pretty-printers</var>. +The value returned is unspecified. +</p></dd></dl> + +<dl> +<dt><a name="index-make_002dpretty_002dprinter_002dworker"></a>Scheme Procedure: <strong>make-pretty-printer-worker</strong> <em>display-hint to-string children</em></dt> +<dd><p>Return an object of type <code><gdb:pretty-printer-worker></code>. +</p> +<p>This function takes three parameters: +</p> +<dl compact="compact"> +<dt>‘<samp>display-hint</samp>’</dt> +<dd><p><var>display-hint</var> provides a hint to <small>GDB</small> or <small>GDB</small> +front end via MI to change the formatting of the value being printed. +The value must be a string or <code>#f</code> (meaning there is no hint). +Several values for <var>display-hint</var> +are predefined by <small>GDB</small>: +</p> +<dl compact="compact"> +<dt>‘<samp>array</samp>’</dt> +<dd><p>Indicate that the object being printed is “array-like”. The CLI +uses this to respect parameters such as <code>set print elements</code> and +<code>set print array</code>. +</p> +</dd> +<dt>‘<samp>map</samp>’</dt> +<dd><p>Indicate that the object being printed is “map-like”, and that the +children of this value can be assumed to alternate between keys and +values. +</p> +</dd> +<dt>‘<samp>string</samp>’</dt> +<dd><p>Indicate that the object being printed is “string-like”. If the +printer’s <code>to-string</code> function returns a Guile string of some +kind, then <small>GDB</small> will call its internal language-specific +string-printing function to format the string. For the CLI this means +adding quotation marks, possibly escaping some characters, respecting +<code>set print elements</code>, and the like. +</p></dd> +</dl> + +</dd> +<dt>‘<samp>to-string</samp>’</dt> +<dd><p><var>to-string</var> is either a function of one parameter, the +<code><gdb:pretty-printer-worker></code> object, or <code>#f</code>. +</p> +<p>When printing from the CLI, if the <code>to-string</code> method exists, +then <small>GDB</small> will prepend its result to the values returned by +<code>children</code>. Exactly how this formatting is done is dependent on +the display hint, and may change as more hints are added. Also, +depending on the print settings (see <a href="Print-Settings.html#Print-Settings">Print Settings</a>), the CLI may +print just the result of <code>to-string</code> in a stack trace, omitting +the result of <code>children</code>. +</p> +<p>If this method returns a string, it is printed verbatim. +</p> +<p>Otherwise, if this method returns an instance of <code><gdb:value></code>, +then <small>GDB</small> prints this value. This may result in a call to +another pretty-printer. +</p> +<p>If instead the method returns a Guile value which is convertible to a +<code><gdb:value></code>, then <small>GDB</small> performs the conversion and prints +the resulting value. Again, this may result in a call to another +pretty-printer. Guile scalars (integers, floats, and booleans) and +strings are convertible to <code><gdb:value></code>; other types are not. +</p> +<p>Finally, if this method returns <code>#f</code> then no further operations +are peformed in this method and nothing is printed. +</p> +<p>If the result is not one of these types, an exception is raised. +</p> +<p><var>to-string</var> may also be <code>#f</code> in which case it is left to +<var>children</var> to print the value. +</p> +</dd> +<dt>‘<samp>children</samp>’</dt> +<dd><p><var>children</var> is either a function of one parameter, the +<code><gdb:pretty-printer-worker></code> object, or <code>#f</code>. +</p> +<p><small>GDB</small> will call this function on a pretty-printer to compute the +children of the pretty-printer’s value. +</p> +<p>This function must return a <gdb:iterator> object. +Each item returned by the iterator must be a tuple holding +two elements. The first element is the “name” of the child; the +second element is the child’s value. The value can be any Guile +object which is convertible to a <small>GDB</small> value. +</p> +<p>If <var>children</var> is <code>#f</code>, <small>GDB</small> will act +as though the value has no children. +</p> +<p>Children may be hidden from display based on the value of ‘<samp>set +print max-depth</samp>’ (see <a href="Print-Settings.html#Print-Settings">Print Settings</a>). +</p></dd> +</dl> +</dd></dl> + +<p><small>GDB</small> provides a function which can be used to look up the +default pretty-printer for a <code><gdb:value></code>: +</p> +<dl> +<dt><a name="index-default_002dvisualizer"></a>Scheme Procedure: <strong>default-visualizer</strong> <em>value</em></dt> +<dd><p>This function takes a <code><gdb:value></code> object as an argument. If a +pretty-printer for this value exists, then it is returned. If no such +printer exists, then this returns <code>#f</code>. +</p></dd></dl> + +<hr> +<div class="header"> +<p> +Next: <a href="Selecting-Guile-Pretty_002dPrinters.html#Selecting-Guile-Pretty_002dPrinters" accesskey="n" rel="next">Selecting Guile Pretty-Printers</a>, Previous: <a href="Types-In-Guile.html#Types-In-Guile" accesskey="p" rel="previous">Types 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> |