\ checkmathlib 05.8.8 NAB
\ Test for the presence of MathLib,
\ exit gracefully with an alert
\ if not present.
needs MathLib
needs zstrings

: m? ( -- )
\ Try a MathLib function.
\ Throws -21 if not present.
  (dfloat) 0 MthLabs dfdrop ;

: go
  MainForm
\ do-ini is required in any
\  app that uses MathLib:
  do-ini
  ['] m? catch if
    0.
    z" MathLib is required to run this application." drop >abs
    z" Visit http://www.radiks.net/~rhuebner/mathlib.html" drop >abs
\ 1005 is the built-in custom error alert:
    1005 FrmCustomAlert
    (bye)
  then
  ." MathLib is present."
  begin ekey drop again ;