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Public domain. 0059 Originally written by Jim Hefferon and Karl Berry, 2018. */ 0060 0061 /* So you can style for yourself */ 0062 @import url("/css/latexreflocal.css"); 0063 0064 0065 0066 a.summary-letter {text-decoration: none} 0067 blockquote.indentedblock {margin-right: 0em} 0068 blockquote.smallindentedblock {margin-right: 0em; font-size: smaller} 0069 blockquote.smallquotation {font-size: smaller} 0070 div.display {margin-left: 3.2em} 0071 div.example {margin-left: 3.2em} 0072 div.lisp {margin-left: 3.2em} 0073 div.smalldisplay {margin-left: 3.2em} 0074 div.smallexample {margin-left: 3.2em} 0075 div.smalllisp {margin-left: 3.2em} 0076 kbd {font-style: oblique} 0077 pre.display {font-family: inherit} 0078 pre.format {font-family: inherit} 0079 pre.menu-comment {font-family: serif} 0080 pre.menu-preformatted {font-family: serif} 0081 pre.smalldisplay {font-family: inherit; font-size: smaller} 0082 pre.smallexample {font-size: smaller} 0083 pre.smallformat {font-family: inherit; font-size: smaller} 0084 pre.smalllisp {font-size: smaller} 0085 span.nolinebreak {white-space: nowrap} 0086 span.roman {font-family: initial; font-weight: normal} 0087 span.sansserif {font-family: sans-serif; font-weight: normal} 0088 ul.no-bullet {list-style: none} 0089 BODY { 0090 margin-top: 1em; 0091 margin-left: 1em; /* auto results in two-digit <ol> lost off left */ 0092 margin-right: 1em; 0093 margin-bottom: 1em; 0094 /* the idea is to use the whole window, unless it is ridiculously 0095 wide, probably with too-small fonts, too. */ 0096 max-width: 64em; 0097 } 0098 0099 /* Because we want @math{... @code ...} to be upright, not slanted, 0100 and Texinfo won't fix it. */ 0101 code {font-style:normal; font-family:monospace; } 0102 0103 /* We put a link to our own home page at the bottom. */ 0104 div.referenceinfo {font-size:small;} 0105 0106 --> 0107 </style> 0108 0109 0110 </head> 0111 0112 <body lang="en"> 0113 <a name="g_t_005cmakeatletter-_0026-_005cmakeatother"></a> 0114 <div class="header"> 0115 <p> 0116 Next: <a href="_005c_0040ifstar.html#g_t_005c_0040ifstar" accesskey="n" rel="next">\@ifstar</a>, Previous: <a href="_005cprovidecommand.html#g_t_005cprovidecommand" accesskey="p" rel="prev">\providecommand</a>, Up: <a href="Definitions.html#Definitions" accesskey="u" rel="up">Definitions</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="IndexDocument.html#Index" title="Index" rel="index">Index</a>]</p> 0117 </div> 0118 <hr> 0119 <a name="g_t_005cmakeatletter-_0026-_005cmakeatother-1"></a> 0120 <h3 class="section">12.3 <code>\makeatletter</code> & <code>\makeatother</code></h3> 0121 0122 <p>Synopsis: 0123 </p> 0124 <div class="example"> 0125 <pre class="example">\makeatletter 0126 ... definition of commands with @ in their name .. 0127 \makeatother 0128 </pre></div> 0129 0130 <p>Use this pair when you redefine LaTeX commands that are named with an 0131 at-sign character ‘<samp><code>@</code></samp>’. The <code>\makeatletter</code> 0132 declaration makes the at-sign character have the category code of a 0133 letter, code 11. The <code>\makeatother</code> declaration sets the 0134 category code of the at-sign to code 12, its default value. 0135 </p> 0136 <p>As TeX reads characters, it assigns each one a category code, or 0137 <a name="index-catcode"></a> 0138 <a name="index-character-category-code"></a> 0139 <a name="index-category-code_002c-character"></a> 0140 <em>catcode</em>. For instance, it assigns the backslash 0141 character ‘<samp><code>\</code></samp>’ the catcode 0. Command names 0142 consist of a category 0 character, ordinarily backslash, followed 0143 by letters, category 11 characters (except that a command name can 0144 also consist of a category 0 character followed by a single 0145 non-letter symbol). 0146 </p> 0147 <p>LaTeX’s source code has the convention that some commands use 0148 <code>@</code> in their name. These commands are mainly intended for package 0149 or class writers. The convention prevents authors who are just using a 0150 package or class from accidentally replacing such a command with one of 0151 their own, because by default the at-sign has catcode 12. 0152 </p> 0153 <p>The pair <code>\makeatletter</code> and <code>\makeatother</code> changes the 0154 default code and then changes it back. Use them inside a <samp>.tex</samp> 0155 file, in the preamble, when you are defining or redefining commands 0156 named with <code>@</code>, by having them surround your definition. Don’t 0157 use these inside <samp>.sty</samp> or <samp>.cls</samp> files since the 0158 <code>\usepackage</code> and <code>\documentclass</code> commands already arrange 0159 that the at-sign has the character code of a letter, catcode 11. 0160 </p> 0161 <a name="index-package_002c-macros2e"></a> 0162 <a name="index-macros2e-package"></a> 0163 0164 <p>For a comprehensive list of macros with an at-sign in their names see 0165 <a href="http://ctan.org/pkg/macros2e">http://ctan.org/pkg/macros2e</a>. 0166 </p> 0167 <p>In this example the class file has a command 0168 <code>\thesis@universityname</code> that the user wants to change. These 0169 three lines should go in the preamble, before the 0170 <code>\begin{document}</code>. 0171 </p> 0172 <div class="example"> 0173 <pre class="example">\makeatletter 0174 \renewcommand{\thesis@universityname}{Saint Michael's College} 0175 \makeatother 0176 </pre></div> 0177 0178 0179 0180 0181 <hr/><div class='referenceinfo'> <a href='https://latexref.xyz/'> <i>Unofficial LaTeX2e reference manual</i></a></div> 0182 </body> 0183 </html>