MiniLOGO

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 Program : MiniLOGO
 Purpose : One-line Implementation of LOGO Turtle Graphics
 Author  : (C) Jon Ripley, 1999-2001
 Version : 0.09 (25th August 2001)
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Commands:

  F <distance> Move turtle forwards <distance>
  B <distance> Move turtle backwards <distance>
  L <angle>    Turn turtle left <angle> degrees
  R <angle>    Turn turtle right <angle> degrees
  H            Home turtle (move to centre of screen)
  P            Toggle Pen Up / Pen Down
  C            Clear screen and home turtle; rest of line is ignored
  X            Exit MiniLOGO
  *<command>   Do *<command>
  : <comment>  Short comment; can be included in compound statements
  | <comment>  Long comment; rest of line is ignored
  ;            Command separator
  <iterations> Repeat command, must be first command in a line

Commands can be upper or lower case. No spaces are required in commands but can
be used anywhere except immediately before a command. Invalid commands have no
effect. Numbers must be in decimal.

Multiple commands on one line can be separated with ';', eg.
f100;r90;f100;r90;f100;r90;f100; The terminating ';' is not required.

Repeat is enabled by prefixing a line with the number of repeats followed by
';', eg. 4;f100;r90;