Redefining \enumerate using \let - why does it behave this way and what can I do to bypass it?

Question

The following code produces a result, that I find quite strange:

\documentclass{article}
\let\origenumerate\enumerate
\renewenvironment{enumerate}{\begin{origenumerate}}{\end{origenumerate}}

\begin{document}

\begin{enumerate}
\item{First}
\begin{enumerate}
    \item{First-1}
    \item{First-2}
\end{enumerate}
\item{Second}
\end{enumerate}

\end{document}

Actual result:

    1. First
        (a) First-1
    (b) First-2
2. Second

Expected result (as without third line in code):

    1. First
        (a) First-1
        (b) First-2
    2. Second

Why is this so? How can I redefine \enurate to use custom \parskip and \itemsep without getting this kind of (bad) jokes?

edit: I am using pdfTeX 3.1415926-2.3-1.40.12 (TeX Live 2011)

There's no need to use braces around each item: you can use \item First instead of \item{First}. — Gonzalo Medina, Jul 28 '11 at 17:41

score 6 · Accepted Answer · answered Jul 28 '11 at 17:18

6

Usually in these cases you need to use the lower-level internal commands for the environment, and also remember about the \end... one. Try

\documentclass{article}
\let\origenumerate\enumerate
\let\origendenumerate\endenumerate
\renewenvironment{enumerate}{\origenumerate}{\origendenumerate}

\begin{document}

\begin{enumerate}
\item{First}
\begin{enumerate}
    \item{First-1}
    \item{First-2}
\end{enumerate}
\item{Second}
\end{enumerate}

\end{document}

answered Jul 28 '11 at 17:18

Joseph Wright

259,911
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You were 5sec faster :-) – Martin Scharrer Jul 28 '11 at 17:19
2

@Andres: See also my answer to Defining environments based on other ones: What's the right way? for an explanation between the higher and lower level form. – Martin Scharrer Jul 28 '11 at 17:20
1

8sec faster, in my case ;-) – Gonzalo Medina Jul 28 '11 at 17:21

score 2 · Answer 2 · answered Jul 28 '11 at 17:39

2

If all you want to do is change the spacing, a package like enumitem is probably safer than this kind of low level hacking.

answered Jul 28 '11 at 17:39

Seamus

73,242

1

\enumitem is probably the one to use. See this for a comparrison between paralist and enumitem – Peter Grill Jul 28 '11 at 17:56

Redefining \enumerate using \let - why does it behave this way and what can I do to bypass it?

2 Answers2