Finally only Scanner>>xBinary need a one line change to allow $- in binary 
selector and preserve the way negated literals are formed without 
ambiguity... Really simple.

You can find it at http://bugs.impara.de/view.php?id=3616

Nicolas


Le Samedi 13 Mai 2006 10:05, nicolas cellier a écrit :
> Let us look inside Parser:
>
> $- except as first binary character is forbidden in Scanner>>xBinary
> Thus '1 +- 2' will scan successive tokens (1) (#+) (#-) (2).
> This will be parsed with Parser>>messagePart:repeat:
> Then Parser>>primaryException will gather (#-) (2) into (LiteralNode value:
> -2)
>
> Without a space  '1+-2' will scan same 4 tokens (1) (#+) (#-) (2), and
> result will be the same.
>
> However, inside literal quotes, space are significant in current
> implementation:
> #(1 - 2) will answer (Array with: 1 with: #- with: 2),
> #(1-2) will be scanned and parsed into (Array with: 1 with: -2).
>
> Concatenating - and 2 as a single token occur in Scanner>>scanLitVec if and
> only if char following - is a digit...
>
> I know how to change this:
> - move token concatenation from #scanLitVec to #scanToken
> - remove #- handling in #primaryExpression
> - remove limitation in #xBinary
>
> But then, this will change semantics of #(1--2) that will be parsed #(1
> #'--' 2) instead of #(1 #- -2).
> We can also make a special handling in xBinary and not groke last - when
> immediately followed with a digit, and raise a Warning exception with
> defaultAction doNothing, but wich could be caught in Parser to warn user of
> possible ambiguity if interactive...
>
> Thus we would keep most compatibility with current implementation.
>
> What do squeakers think of this change ?
>
> Nicolas