boldmacros
I use LaTeX mostly for homework assignments. And I would like a faster way to type
\noindent\textbf{problem number}
Since I do it for every problem and every part of the problem if it has multiple parts.
I was thinking something like this might work, but it isn't:
\newcommand{\HW{}}{\noindent\textbf{}}
I've tried with and without the \textbf brackets.
You can't use ¬ and ¦ as “command chars” if you have \usepackage[utf8]{inputenc}. Only one byte characters can be used for the purpose (and not all of them, actually).
If you are willing to switch to XeLaTeX or LuaLaTeX, then it's possible.
Here is a way, without packages.
\documentclass{article}
\newcommand\bforall[3][r]{%
\ifx r#1\forall #2\, (#3)\else
\ifx s#1\forall #2\, [#3]\else
\ifx c#1\forall #2\, \{#3\}\else
\mathrm{Illegal~option}%
\fi\fi\fi
}
\begin{document}
$\bforall{x}{x \in A}$
$\bforall[r]{x}{x \in A}$
$\bforall[s]{x}{x \in A}$
$\bforall[c]{x}{x \in A}$
\end{document}
As touhami rightly points out, the penalty for using the simplicity of the \ifx construct is that an accidental syntax error such as using a two character optional argument like [rs] will not produce an error message, but rather just wrongly set the term.
Best Answer
You need to use the following format:
Note that I haven't captured the argument, since
\textbfwill do this when used as the replacement of\HW. Of course, you can capture and pass the argument if needed viaThe only different between these two definitions would be if you had category code changes within the argument.