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diff --git a/share/doc/cpp/Macros.html b/share/doc/cpp/Macros.html new file mode 100644 index 0000000..9fb338b --- /dev/null +++ b/share/doc/cpp/Macros.html @@ -0,0 +1,122 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1987-2023 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. A copy of +the license is included in the +section entitled "GNU Free Documentation License". + +This manual contains no Invariant Sections. The Front-Cover Texts are +(a) (see below), and the Back-Cover Texts are (b) (see below). + +(a) The FSF's Front-Cover Text is: + +A GNU Manual + +(b) The FSF's Back-Cover Text is: + +You have freedom to copy and modify this GNU Manual, like GNU + software. Copies published by the Free Software Foundation raise + funds for GNU development. --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>The C Preprocessor: Macros</title> + +<meta name="description" content="The C Preprocessor: Macros"> +<meta name="keywords" content="The C Preprocessor: Macros"> +<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="Index-of-Directives.html#Index-of-Directives" rel="index" title="Index of Directives"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="index.html#Top" rel="up" title="Top"> +<link href="Object_002dlike-Macros.html#Object_002dlike-Macros" rel="next" title="Object-like Macros"> +<link href="System-Headers.html#System-Headers" rel="previous" title="System Headers"> +<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="Macros"></a> +<div class="header"> +<p> +Next: <a href="Conditionals.html#Conditionals" accesskey="n" rel="next">Conditionals</a>, Previous: <a href="Header-Files.html#Header-Files" accesskey="p" rel="previous">Header Files</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index-of-Directives.html#Index-of-Directives" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Macros-1"></a> +<h2 class="chapter">3 Macros</h2> + +<p>A <em>macro</em> is a fragment of code which has been given a name. +Whenever the name is used, it is replaced by the contents of the macro. +There are two kinds of macros. They differ mostly in what they look +like when they are used. <em>Object-like</em> macros resemble data objects +when used, <em>function-like</em> macros resemble function calls. +</p> +<p>You may define any valid identifier as a macro, even if it is a C +keyword. The preprocessor does not know anything about keywords. This +can be useful if you wish to hide a keyword such as <code>const</code> from an +older compiler that does not understand it. However, the preprocessor +operator <code>defined</code> (see <a href="Defined.html#Defined">Defined</a>) can never be defined as a +macro, and C++’s named operators (see <a href="C_002b_002b-Named-Operators.html#C_002b_002b-Named-Operators">C++ Named Operators</a>) cannot be +macros when you are compiling C++. +</p> +<table class="menu" border="0" cellspacing="0"> +<tr><td align="left" valign="top">• <a href="Object_002dlike-Macros.html#Object_002dlike-Macros" accesskey="1">Object-like Macros</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Function_002dlike-Macros.html#Function_002dlike-Macros" accesskey="2">Function-like Macros</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Macro-Arguments.html#Macro-Arguments" accesskey="3">Macro Arguments</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Stringizing.html#Stringizing" accesskey="4">Stringizing</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Concatenation.html#Concatenation" accesskey="5">Concatenation</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Variadic-Macros.html#Variadic-Macros" accesskey="6">Variadic Macros</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Predefined-Macros.html#Predefined-Macros" accesskey="7">Predefined Macros</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Undefining-and-Redefining-Macros.html#Undefining-and-Redefining-Macros" accesskey="8">Undefining and Redefining Macros</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Directives-Within-Macro-Arguments.html#Directives-Within-Macro-Arguments" accesskey="9">Directives Within Macro Arguments</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +<tr><td align="left" valign="top">• <a href="Macro-Pitfalls.html#Macro-Pitfalls">Macro Pitfalls</a>:</td><td> </td><td align="left" valign="top"> +</td></tr> +</table> + + + + +</body> +</html> |