clear
? "with a file"
SET TEXTMERGE TO vText Off
? "before filename",SET("Textmerge",2)
\bla bla
TRY
  =b
CATCH
ENDTRY
? "after filename",SET("Textmerge",2)
\cla cla
SET TEXTMERGE TO
MODIFY FILE vText

? "with a memvar"
SET TEXTMERGE TO memvar vText
\bla bla
TRY
  =b
CATCH
ENDTRY
\cla cla
SET TEXTMERGE TO
? "vText is",vText