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From: ogawa@orion.arc.nasa.gov (Arthur Ogawa)
Newsgroups: comp.text.tex
Subject: Re: Defining new Delimiters in LaTeX math?
Message-ID: <1991Mar6.014620.27972@news.arc.nasa.gov>
Date: 6 Mar 91 01:46:20 GMT
References: <2402@taurus.BITNET>
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In article <2402@taurus.BITNET> raan%math.tau.ac.il@CUNYVM.CUNY.EDU (Ran Ever-Hadani) writes:
|Is there a way to define new delimiters in LaTeX math mode,
|other than the existing () {} <> | etc.?
|
|What I am after is a the semantics meaning delimiters, which
|look something like this:
|
|	=======                   =======
|	|  |                         |  |
|	|  |                         |  |
|	|  |                         |  |
|	|  |                         |  |
|	|  |      Expression         |  |
|	|  |                         |  |
|	|  |                         |  |
|	|  |                         |  |
|	|  |                         |  |
|	|  |                         |  |
|	=======                   =======
|
|Of course, I want it to change size in accordance with the size
|of the expression, as \{ Expression \} would.

Here's my best shot:

 \documentstyle{book}

\def\Lmeaning{\left[\![}%
\def\Rmeaning{\right]\!]}%

\begin{document}
\[
\Lmeaning
Expression
\Rmeaning
\]
\end{document}

You must use these delimiters in pairs because of the \left and \right.