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diff --git a/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-hash.html b/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-hash.html deleted file mode 100644 index 0d74b368834..00000000000 --- a/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-hash.html +++ /dev/null @@ -1,37 +0,0 @@ -<head> -<title>UK TeX FAQ -- question label hash</title> -</head><body> -<h3>Defining macros within macros</h3> -<p/>The way to think of this is that <code>##</code> gets replaced by <code>#</code> in just the -same way that <code>#1</code> gets replaced by ‘whatever is the first argument’. -<p/>So if you define a macro and use it as: -<blockquote> -<pre> -\def\a#1{+++#1+++#1+++#1+++} \a{b} -</pre> -</blockquote><p> -the macro expansion produces ‘+++b+++b+++b+++’, -which people find normal. However, if we now replace part of the macro: -<blockquote> -<pre> -\def\a#1{+++#1+++\def\x #1{xxx#1}} -</pre> -</blockquote><p> -<code>\</code><code>a{b}</code> will expand to ‘+++b+++<code>\def\x b{xxxb}</code>’. This -defines <code>\</code><code>x</code> to be a macro <em>delimited</em> by <code>b</code>, and taking no -arguments, which people may find strange, even though it is just a -specialisation of the example above. If you want <code>\</code><code>a</code> to -define <code>\</code><code>x</code> to be a macro with one argument, you need to write: -<blockquote> -<pre> -\def\a#1{+++#1+++\def\x ##1{xxx##1}} -</pre> -</blockquote><p> -and <code>\</code><code>a{b</code>} will expand to -‘+++b+++<code>\def\x #1{xxx#1}</code>’, because <code>#1</code> gets replaced by ‘b’ -and <code>##</code> gets replaced by <code>#</code>. -<p/>To nest a definition inside a definition inside a definition then -you need <code>####1</code>, as at each stage <code>##</code> is replaced by -<code>#</code>. At the next level you need 8 <code>#</code>s each time, and so on. -<p/><p>This question on the Web: <a href="http://www.tex.ac.uk/cgi-bin/texfaq2html?label=hash">http://www.tex.ac.uk/cgi-bin/texfaq2html?label=hash</a> -</body> |