On Wed, 5 Sep 2018 15:57:16 +0200 Dieter <d.gloetzel at web.de> wrote: > I only half-understand, what Wirth writes on trees in his green > Oberonbook. Hi, I wonder what is this `Green Book'? Is it the one titled `Steps beyond Pascal and Modula? -- Tomas Kral <thomas.kral at email.cz>