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diff --git a/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-plninltxstar.html b/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-plninltxstar.html new file mode 100644 index 00000000000..e82af36e735 --- /dev/null +++ b/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-plninltxstar.html @@ -0,0 +1,52 @@ +<head> +<title>UK TeX FAQ -- question label plninltx*</title> +</head><body> +<h3>Using Plain or primitive commands in LaTeX</h3> +<p/>It’s well-known that LaTeX commands tend to be more complex, and to +run more slowly than, any Plain (or primitive) command that they +replace. There is therefore great temptation not to use LaTeX +commands when macro programming. Nevertheless, the general rule is +that you should use LaTeX commands, if there are seeming +equivalents. The exception is when you are sure you know the +differences between the two commands and you know that you need the +Plain version. So, for example, use <code>\</code><code>mbox</code> in place of <code>\</code><code>hbox</code> +unless you know that the extras that LaTeX provides in <code>\</code><code>mbox</code> +would cause trouble in your application. Similarly, use +<code>\</code><code>newcommand</code> (or one of its relatives) unless you need one of the +constructs that cannot be achieved without the use of <code>\</code><code>def</code> (or friends). +<p/>As a general rule, any LaTeX text command will start a new +paragraph if necessary; this isn’t the case with Plain TeX +commands, a fact which has a potential to confuse. +<p/>The commands <code>\</code><code>smallskip</code>, <code>\</code><code>medskip</code> and <code>\</code><code>bigskip</code> exist both +in Plain TeX and LaTeX, but behave slightly differently: in Plain +TeX they terminate the current paragraph, but in LaTeX they +don’t. The command <code>\</code><code>line</code> is part of picture mode in LaTeX, +whereas it’s defined as “<code>\</code><code>hbox</code><code> to </code><code>\</code><code>hsize</code>” in +Plain TeX. (There’s no equivalent for users of the Plain TeX command in +LaTeX: an equivalent appears as the internal command <code>\</code><code>@@line</code>). +<p/>Maths setting shows a case where the LaTeX version <em>is</em> +essentially equivalent to the TeX primitive commands: the LaTeX +<code>\</code><code>(</code><code> ... </code><code>\</code><code>)</code> does essentially no different to the +TeX <code>$ ... $</code> +(except for checking that you’re not attempting to open a maths +environment when you’re already in one, or vice versa). +However, <code>\</code><code>[</code><code> ... </code><code>\</code><code>]</code> <em>isn’t</em> the same as +<code>$$ ... $$</code>: the TeX version, used +in LaTeX, can miss the effect of the class option <code>fleqn</code>. +<p/>Font handling is, of course, wildly different in Plain TeX and +LaTeX. Plain TeX’s font loading command +(<code>\</code><code>font</code><code>\</code><code>foo=</code><<i>fontname</i>>) and its LaTeX equivalent +(<code>\</code><code>newfont</code>) should be avoided wherever possible. They are only +safe in the most trivial contexts, and aer potential sources of great +confusion in many circumstances. Further discussion of this issue +may be found in “<a href="FAQ-newfontstar.html">What’s wrong with <code>\</code><code>newfont</code>?</a>”. + + + + + + + + +<p/><p>This question on the Web: <a href="http://www.tex.ac.uk/cgi-bin/texfaq2html?label=plninltx*">http://www.tex.ac.uk/cgi-bin/texfaq2html?label=plninltx*</a> +</body> |