Re: LOGO-L> one small problem

[Yehuda Katz <yehuka@beitberl.beitberl.ac.il>]

At 08:05 PM 6/30/97 +0200, you wrote:
>Hi folks,
>
>I want to remove from a word the first and last letter every time I call a
>recursive function.
>So ... MSWLOGO
>        SWLOG
>         WLO
>          L
>
>I write the following procedure
>
>to remove :wrd
>if emptyp :wrd [stop]
>print :wrd
>remove bf bl :wrd
>end
>
>When the procedure gets to the last letter (L), I get a error message
>" .... Logo doesn't like [] as an input for bf .... ".
>I understand the error. But how do I fix it?
>
>Regards,
>Harrie
>H.Hoenjet@inter.NL.net


Harrie,

Just say:

to remove :wrd
if 2>count :wrd [stop]
print :wrd
remove bf bl :wrd
end

Reason: MSWLOGO consists of an ODD number of letters. When eventually you
remain with a single letter, you can't ask for the BF BL :WRD of it, as it
becomes empty after BL :WRD, and Logo can't go on and perform the BF of an
empty word.

Your program works perfectly with a word of an even number of letters.

Regards...

[[Yehuda]]

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