[texhax] skip after/before environment

[Victor Ivrii]

I use environment claim introduced by

\newenvironment{claim}[1][{\rm(\theequation)}]{\refstepcounter{equation}\vglue10pt
\begin{trivlist}
\item[{\hskip\labelsep#1}]}{\end{trivlist}\vglue10pt}


so it is a piece of the regular (mathematical) text, separated from
the rest by two vskips and numbered as if it was an equation.

The trouble comes if either I use

\begin{claim}
blah-blah-blah-blah-blah-blah-blah-blah-
\end{claim}
\begin{claim}
blah-blah-blah-blah-blah-blah-blah-blah-
\end{claim}


then the distance between these claims is too large (fixing it
manually by negative vskip is not a regular thing) or if

\begin{claim}
blah-blah-blah-blah-blah-blah-blah-blah-
\begin{equation}
1+1=2
\end{equation}
\end{claim}
ho-ho-ho

when the distance between equation in the end of claim and the next
line is too large again and again fixing it manually by negative vskip
is not a regular thing.

Is there any way to modify my definition of environment to fix this
problem. Thank you in advance

-- 
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Victor Ivrii, Department of Mathematics, University of Toronto