Hi John,
thank you for our reply it is really helpful.
Can you please also spend a bit of your time to talk about the “permissiveness"
of the pattern syntax. For example the string '`.head `.@tail’ is parsed into a
message node with selector `.@tail and a receiver variable node `.head. To my
knowledge this is not a valid syntax as the names that have a dot in the
beginning should become matchers for statements. Also for example if you write
`#@literal the list marker is not doing anything when combines with the literal
pound as far as I know, and some people are confused about this, were the any
reason why this is not simply rising a syntax error?
Cheers.
Uko
> On 11 Dec 2016, at 00:46, John Brant <br...@refactoryworkers.com> wrote:
>
> On 12/10/2016 02:37 AM, Nicolai Hess wrote:
>
>> Question : how should a pattern with three variables
>> (first/second/third) look like to match the expression
>> { (1@2) . Color red . 3} and assign the (sub)-expressions
>> 1@2
>> Color red
>> 3
>> to the three variables first/second/third ?
>
> The RB was written before the {} array syntax. It appears that are a few bugs
> in the pattern matching for the arrays. The first is that it needs to reset
> the isList variable of RBPatternVariableNode when it is part of a dynamic
> array. You can fix that by adding this to the end of
> RBPatternVariableNode>>parent: method:
>
> parent isDynamicArray
> ifTrue: [ self isStatement
> ifFalse: [ isList := false ] ]
>
> I think this will make the matching work like what you are expecting. If you
> want to match multiple statements, you need to add a ".", but if you just
> have "`@first", it will only match any expression node.
>
> While testing I noticed an error in the RBArrayNode>>match:inContext:. The
> method doesn't test the lengths of the nodes before sending the #with:do:
> message. If you try to match two arrays of different sizes, you get an error.
> This should be changed back to be:
>
> match: aNode inContext: aDictionary
> aNode class = self class
> ifFalse: [ ^ false ].
> ^ self matchList: statements against: aNode statements inContext:
> aDictionary
>
>
> John Brant
>
