!set methtit=表达式内的替换
!set methtit2=整体表达式内的替换
!set methenv=ZZ QQ RR CC
!set methparmtype=parm algexp nocomma nopart, parm equation >, choice 2
!set methhelp=根据已有等式在表达式内作替换.

!if $wims_read_parm iswordof form check
 !goto $wims_read_parm
!endif

!exit
:form
 应用
 !formselect methparm3 list 1,2 prompt 替换, 逆替换
 !read deduc/methparm.phtml 2
 于表达式 <br/>
 !read deduc/methparm.phtml 1
!exit
:check
 !distribute items $methparmobj2 into hd,left,eq,right
 eqt==
 !if $eq!=$eqt
  error=错的替换.
  !exit
 !endif
 !if $methparm3=2
  !exchange left,right
 !endif
 lvar=!varlist $left
 !if $lvar=$left
  subst=subst
 !else
  subst=ratsubst
 !endif
 !distribute items $methparmobj1 into hd2,exp2
 !read deduc/sub/simplify $subst($right,$left,$exp2)
 !if $out=$empty
  error=失败
  !exit
 !endif

 newobject1=$out
 oldobject=1
 methexp=替换 \($left = $right).
!exit

