Thanks to both Avi and Richard for taking the time to help me out.  I was
confused with ifTrue: and IfFalse, I, (half), remembered that it was
considered better style to bracket your boolean conditions to make things
slightly more readable;  but a whileTrue: is not the same as ifTrue:
though... ;-)

Once running I found that it was extremely slow with Transcript show:
(probably because the chars had to be converted to strings and then
flushed), changing things to nextPut: really sped things up.  The current
method code is below. Can anyone suggest anything else I could improve to
make it more 'Squeak-Like'  - I was thinking that sunit tests and a little
refactoring would be useful next step.

    "Generate a MandelBrot image using only ASCII characters."
    | d r n h |
    Transcript show: Character cr.
    1.1
        to: -1.1001
        by: -0.1
        do: [:e | 
            -2.0
                to: 0.9601
                by: 0.04
                do: [:b |
                    r := 0.0.
                    n := 0.0.
                    h := 127.
                    [r * r + (n * n) < 4.0
                        and: [h > 32]]
                        whileTrue: [h := h - 1.
                            d := r.
                            r := r * r - (n * n) + b.
                            n := 2 * d * n + e].
                    Transcript
                        nextPut: (Character
                                value: (b > 1
                                        ifTrue: [13]
                                        ifFalse: [h]))].
            Transcript show: Character cr]

Thanks again :-)

Chris

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