我正在使用该mathpartir包的inferrule宏，当涉及到“普通”文档类别（文章、书籍）时，它非常适合我的需求。
但是，当尝试使用 beamer 文档类时，即inferrule在演示文稿中重复使用我的部分时，前提不再包含任何换行符。通常，inferrule如果前提太多，或者您明确指定，则会中断前提并将新的前提放在另一行。在环境\\\\中使用它时，两者似乎都会被忽略。frame
有没有办法可以设置基于 beamer 的文件，以便我可以直接inferrule从文章中重复使用（复制和粘贴）我的宏？
下面是一个展示该问题的小示例文档：
\documentclass{beamer}
\usepackage{times}
\usepackage{mathpartir}
\begin{document}
\begin{frame}
\frametitle{Why no breaks?}
\begin{mathpar}
\inferrule{a\\\\b}{c}
\end{mathpar}
\end{frame}
\end{document}
答案1
我对你为 beamer 或 article 举的例子没有任何问题，输出相同。我的文件列表（\listfiles 作为第一行）
*File List*
beamer.cls 2010/06/21 development version 3.10 A class for typesetting pre
sentations (rcs-revision a6b1a8434d30)
beamerbasercs.sty 2010/06/12 (rcs-revision c3821710bb40)
beamerbasemodes.sty 2010/05/01 (rcs-revision efa082c6111d)
beamerbasedecode.sty 2010/05/01 (rcs-revision efa082c6111d)
beamerbaseoptions.sty 2010/04/27 (rcs-revision 982469101dd6)
keyval.sty 1999/03/16 v1.13 key=value parser (DPC)
geometry.sty 2010/09/12 v5.6 Page Geometry
ifpdf.sty 2011/01/30 v2.3 Provides the ifpdf switch (HO)
ifvtex.sty 2010/03/01 v1.5 Switches for detecting VTeX and its modes (HO)
ifxetex.sty 2010/09/12 v0.6 Provides ifxetex conditional
size11.clo 2007/10/19 v1.4h Standard LaTeX file (size option)
pgfcore.sty 2010/04/11 v2.10 (rcs-revision 1.7)
graphicx.sty 1999/02/16 v1.0f Enhanced LaTeX Graphics (DPC,SPQR)
graphics.sty 2009/02/05 v1.0o Standard LaTeX Graphics (DPC,SPQR)
trig.sty 1999/03/16 v1.09 sin cos tan (DPC)
graphics.cfg 2010/04/23 v1.9 graphics configuration of TeX Live
pdftex.def 2011/04/25 v0.06b Graphics/color for pdfTeX
infwarerr.sty 2010/04/08 v1.3 Providing info/warning/message (HO)
ltxcmds.sty 2011/04/18 v1.20 LaTeX kernel commands for general use (HO)
pgfsys.sty 2010/06/30 v2.10 (rcs-revision 1.37)
pgfrcs.sty 2010/10/25 v2.10 (rcs-revision 1.24)
everyshi.sty 2001/05/15 v3.00 EveryShipout Package (MS)
pgfrcs.code.tex
pgfsys.code.tex
pgfsyssoftpath.code.tex 2008/07/18 (rcs-revision 1.7)
pgfsysprotocol.code.tex 2006/10/16 (rcs-revision 1.4)
xcolor.sty 2007/01/21 v2.11 LaTeX color extensions (UK)
color.cfg 2007/01/18 v1.5 color configuration of teTeX/TeXLive
pgfcore.code.tex
xxcolor.sty 2003/10/24 ver 0.1
hyperref.sty 2011/04/17 v6.82g Hypertext links for LaTeX
hobsub-hyperref.sty 2011/04/23 v1.4 Bundle oberdiek, subset hyperref (HO)
hobsub-generic.sty 2011/04/23 v1.4 Bundle oberdiek, subset generic (HO)
hobsub.sty 2011/04/23 v1.4 Subsetting bundle oberdiek (HO)
ifluatex.sty 2010/03/01 v1.3 Provides the ifluatex switch (HO)
intcalc.sty 2007/09/27 v1.1 Expandable integer calculations (HO)
etexcmds.sty 2011/02/16 v1.5 Prefix for e-TeX command names (HO)
kvsetkeys.sty 2011/04/07 v1.13 Key value parser (HO)
kvdefinekeys.sty 2011/04/07 v1.3 Defining keys (HO)
pdftexcmds.sty 2011/04/22 v0.16 Utilities of pdfTeX for LuaTeX (HO)
pdfescape.sty 2011/04/04 v1.12 Provides string conversions (HO)
bigintcalc.sty 2011/01/30 v1.2 Expandable big integer calculations (HO)
bitset.sty 2011/01/30 v1.1 Data type bit set (HO)
uniquecounter.sty 2011/01/30 v1.2 Provides unlimited unique counter (HO)
letltxmacro.sty 2010/09/02 v1.4 Let assignment for LaTeX macros (HO)
hopatch.sty 2011/01/30 v1.0 Wrapper for package hooks (HO)
xcolor-patch.sty 2011/01/30 xcolor patch
atveryend.sty 2011/04/23 v1.7 Hooks at very end of document (HO)
atbegshi.sty 2011/01/30 v1.15 At begin shipout hook (HO)
refcount.sty 2010/12/01 v3.2 Data extraction from references (HO)
hycolor.sty 2011/01/30 v1.7 Color options of hyperref/bookmark (HO)
kvoptions.sty 2010/12/23 v3.10 Keyval support for LaTeX options (HO)
pd1enc.def 2011/04/17 v6.82g Hyperref: PDFDocEncoding definition (HO)
hyperref.cfg 2002/06/06 v1.2 hyperref configuration of TeXLive
url.sty 2006/04/12 ver 3.3 Verb mode for urls, etc.
hpdftex.def 2011/04/17 v6.82g Hyperref driver for pdfTeX
rerunfilecheck.sty 2011/04/15 v1.7 Rerun checks for auxiliary files (HO)
beamerbaserequires.sty 2010/05/01 (rcs-revision efa082c6111d)
beamerbasecompatibility.sty 2010/07/12 (rcs-revision 6648c3177e4e)
beamerbasefont.sty 2010/05/10 (rcs-revision cd36e8a33c6b)
amssymb.sty 2009/06/22 v3.00
amsfonts.sty 2009/06/22 v3.00 Basic AMSFonts support
beamerbasetranslator.sty 2010/06/11 (rcs-revision 85fd1cc7fc42)
translator.sty 2010/06/12 ver 1.10
translator-language-mappings.tex
beamerbasemisc.sty 2010/06/06 (rcs-revision bff0a9294b45)
beamerbasetwoscreens.sty 2010/05/01 (rcs-revision efa082c6111d)
beamerbaseoverlay.sty 2010/05/07 (rcs-revision 5584dad462a9)
beamerbasetitle.sty 2010/06/12 (rcs-revision 717e481ca47a)
beamerbasesection.sty 2010/06/17 (rcs-revision e0d9401bb743)
beamerbaseframe.sty 2010/06/06 (rcs-revision bff0a9294b45)
beamerbaseverbatim.sty 2010/05/01 (rcs-revision efa082c6111d)
beamerbaseframesize.sty 2010/06/27 (rcs-revision 6baa2d92e6f1)
beamerbaseframecomponents.sty 2010/07/12 (rcs-revision 09e82992d9b1)
beamerbasecolor.sty 2010/06/06 (rcs-revision d1a9b48be06d)
beamerbasenotes.sty 2010/05/01 (rcs-revision efa082c6111d)
beamerbasetoc.sty 2010/06/11 (rcs-revision 242ecaa6783b)
beamerbasetemplates.sty 2010/05/01 (rcs-revision efa082c6111d)
beamerbaseauxtemplates.sty 2010/05/01 (rcs-revision efa082c6111d)
beamerbaseboxes.sty 2010/05/01 (rcs-revision efa082c6111d)
beamerbaselocalstructure.sty 2010/06/01 (rcs-revision 81f9e33f7cc2)
enumerate.sty 1999/03/05 v3.00 enumerate extensions (DPC)
beamerbasenavigation.sty 2010/05/01 (rcs-revision efa082c6111d)
beamerbasetheorems.sty 2010/06/06 (rcs-revision 7e7cc5e53e9d)
amsmath.sty 2000/07/18 v2.13 AMS math features
amstext.sty 2000/06/29 v2.01
amsgen.sty 1999/11/30 v2.0
amsbsy.sty 1999/11/29 v1.2d
amsopn.sty 1999/12/14 v2.01 operator names
amsthm.sty 2009/07/02 v2.20.1
beamerbasethemes.sty 2010/05/01 (rcs-revision efa082c6111d)
beamerthemedefault.sty 2010/06/17 (rcs-revision d02a7cf4d8ae)
beamerfontthemedefault.sty 2010/06/17 (rcs-revision d02a7cf4d8ae)
beamercolorthemedefault.sty 2010/06/17 (rcs-revision d02a7cf4d8ae)
beamerinnerthemedefault.sty 2010/06/17 (rcs-revision d02a7cf4d8ae)
beamerouterthemedefault.sty 2010/06/17 (rcs-revision d02a7cf4d8ae)
times.sty 2005/04/12 PSNFSS-v9.2a (SPQR)
mathpartir.sty 2005/12/20 version 1.2.0 Math Paragraph for Typesetting Infer
ence Rules
ot1phv.fd 2001/06/04 scalable font definitions for OT1/phv.
supp-pdf.mkii
epstopdf-base.sty 2010/02/09 v2.5 Base part for package epstopdf
grfext.sty 2010/08/19 v1.1 Managing graphics extensions (HO)
epstopdf-sys.cfg 2010/07/13 v1.3 Configuration of (r)epstopdf for TeX Live
nameref.sty 2010/04/30 v2.40 Cross-referencing by name of section
gettitlestring.sty 2010/12/03 v1.4 Cleanup title references (HO)
test.out
test.out
translator-basic-dictionary-English.dict
translator-bibliography-dictionary-English.dict
translator-environment-dictionary-English.dict
translator-months-dictionary-English.dict
translator-numbers-dictionary-English.dict
translator-theorem-dictionary-English.dict
umsa.fd 2009/06/22 v3.00 AMS symbols A
umsb.fd 2009/06/22 v3.00 AMS symbols B
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