[texhax] skip after/before environment

[Uwe Lück]

At 12:05 08.06.06, Victor Ivrii wrote:
>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.

\vglue10pt should be replaced by \addvspace{10pt} .

Indeed, I consider this possibility one of the greatest advantages
of (La)TeX over that product whose name I have forgotten by that
software company whose name I have forgotten.

However: A \trivlist is surrounded by the \topsep (or even \partopsep)
space anyway -- so you might think that \addvspace{10pt} is wrong.
Doesn't changing \topsep (\partopsep) satisfy you?
(This affects all lists and \trivlist's.) If not, just increase the argument
of \addvspace.

HTH -- Uwe.