58.1 Aligned

We need the ‘\vtop’ within ‘\[...\]’ because of the extra math environment taht we insert.

<..equations of amstex1..>
                                     \catcode‘\#=13 \catcode‘\!=6
 \def\reg:aligned@{\bgroup
   \vspace@\Let@ \everycr{}%
   \SaveMkHalignConf:g{aligned:type}%\HRestore\noalign
   \MkHalign#{<.amstex1 aligned@ pattern.>}%
 }
                                     \catcode‘\#=6 \catcode‘\!=12
 -_-_-

<..amstex1 aligned@ pattern..>
 $\m@th\displaystyle{#}$&%
 $\m@th\displaystyle{{}#}$%
 -_-_-

<..equations of amstex1..>+
 \def\:tempc{\crcr\EndMkHalign
    \RecallMkHalignConfig \csname b:\aligned:type\endcsname \egroup}
 \HLet\endaligned=\:tempc
 \def\:temp{\pic:MkHalign{aligned@}}
 \HLet\aligned@=\:temp
 \NewConfigure{aligned}{6}
 \NewConfigure{topaligned}{6}
 \NewConfigure{botaligned}{6}
 \pend:def\topaligned{\def\aligned:type{topaligned}}
 \pend:def\botaligned{\def\aligned:type{botaligned}}
 \pend:def\aligned{\def\aligned:type{aligned}}
 -_-_-