[Tex/LaTex] An enumeration of equations with aligned equal signs

#enumeratealignequationshorizontal alignmentlists

I'd like to have something like the following:

\begin{enumerate}
\item $1 + 1 = 2$ 
\item $1 = 2 - 1$
\end{enumerate}

The thing is, I'd also like the equals signs to be aligned. But I'd like the equation with the widest left side to start out right after the item number, as if that line were text.

Note: What I'm trying to do is state a theorem with several parts, each of which is most easily stated as an equation. Obviously, if I only cared about the minimal working example above, I would be better off using an align environment and equation numbers.
Is there a reasonable way to do this?

Best Answer

\usepackage{array}

\newenvironment{enumalign}
  {\par\addvspace{\topsep}\setcounter{enumi}{0}
   \noindent$\begin{array}{@{}r@{\hspace{\labelsep}}r@{}>{{}}l@{}}}
  {\end{array}$\par\addvspace{\topsep}}
\newcommand{\eitem}{\stepcounter{enumi}\makebox[\labelwidth][r]{\theenumi.}&}

\begin{document}
\begin{enumalign}
\eitem 1+1&=2\\
\eitem 1&=2-1
\end{enumalign}

Remember to end the rows with \\

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