> FUNC fibo(int a) int
>      IF a <= 2
>          RETURN 1
>      ELSE
>          RETURN fibo(a - 1) + fibo(a - 2)
>      }
>      RETURN 0
> }

> FUNC MAIN() int
>       IF ARG.size() != 0
>           IO.write(fibo(ARG.get(0)))
>       ELSE
>           IO.write("Falten arguments\n")
>       }
>    RETURN 0
> }

> produces me an error:

> $ ../zimbu fibonnaci.zu
> fibonnaci.zu line 13 col 13: ERROR: More than one method with matching
> arguments for write(unknown)
> fibonnaci.zu line 721 col 3: ERROR: here
> fibonnaci.zu line 715 col 3: ERROR: and here
> fibonnaci.zu line 13 col 13: ERROR: builtinModule member not found: write

> > FUNC fibo(int a) int
> >      IF a <= 2
> >          RETURN 1
> >      ELSE
> >          RETURN fibo(a - 1) + fibo(a - 2)
> >      }
> >      RETURN 0
> > }

> > FUNC MAIN() int
> >       IF ARG.size() != 0
> >           IO.write(fibo(ARG.get(0)))
> >       ELSE
> >           IO.write("Falten arguments\n")
> >       }
> >    RETURN 0
> > }

> > produces me an error:

> > $ ../zimbu fibonnaci.zu
> > fibonnaci.zu line 13 col 13: ERROR: More than one method with matching
> > arguments for write(unknown)
> > fibonnaci.zu line 721 col 3: ERROR: here
> > fibonnaci.zu line 715 col 3: ERROR: and here
> > fibonnaci.zu line 13 col 13: ERROR: builtinModule member not found: write

> Note that the file names are wrong in the last three errors.  That's a
> known bug.

> The actual error is somehow not printed.  I'll see if I can fix that.

> The problem in your code is that ARG.get(0) returns a string, but the
> fibo() function requires an int.  This will work:

> FUNC MAIN() int
>       IF ARG.size() != 0
>           IO.write(fibo(ARG.get(0).toInt()))
>       ELSE
>           IO.write("Falten arguments\n")
>       }
>    RETURN 0

> }

>  /// Bram Moolenaar -- B...@Moolenaar.net --http://www.Moolenaar.net  \\\
> ///        sponsor Vim, vote for features --http://www.Vim.org/sponsor/\\\
> \\\  an exciting new programming language --http://www.Zimbu.org       ///
>  \\\            help me help AIDS victims --http://ICCF-Holland.org   ///

> > > FUNC fibo(int a) int
> > > IF a <= 2
> > > RETURN 1
> > > ELSE
> > > RETURN fibo(a - 1) + fibo(a - 2)
> > > }
> > > RETURN 0
> > > }

> > > FUNC MAIN() int
> > > IF ARG.size() != 0
> > > IO.write(fibo(ARG.get(0)))
> > > ELSE
> > > IO.write("Falten arguments\n")
> > > }
> > > RETURN 0
> > > }

> > > produces me an error:

> > > $ ../zimbu fibonnaci.zu
> > > fibonnaci.zu line 13 col 13: ERROR: More than one method with matching
> > > arguments for write(unknown)
> > > fibonnaci.zu line 721 col 3: ERROR: here
> > > fibonnaci.zu line 715 col 3: ERROR: and here
> > > fibonnaci.zu line 13 col 13: ERROR: builtinModule member not found: write

> > Note that the file names are wrong in the last three errors. That's a
> > known bug.

> > The actual error is somehow not printed. I'll see if I can fix that.

> Please, fix it.

> > FUNC MAIN() int
> > IF ARG.size() != 0
> > IO.write(fibo(ARG.get(0).toInt()))
> > ELSE
> > IO.write("Falten arguments\n")
> > }
> > RETURN 0

> > }

> Thanks.
> Just a suggestion: invoke IO.write with multiple arguments:
> IO.write("Integer", 3, "is odd")
> now produces an error