Hello Gisela,
On 21 août 2013, at 15:43, Gisela Decuzzi wrote:
> Hello, I'm trying to understand how to define a correct pattern and I'm lost
> with the cases where I use a method pattern and the desired code is inside a
> block.
> In the case where we search (methods) with metavariables and the code is
> inside a block.
>
> An Example:
>
> This pattern
> `a: `aa `b: `bb
> | `@temps |
> ``@.Stats.
> ``@.some size ``@.more.
> ``@.Stats2.
Putting a dot after the @ means that you want to match statements.
So '``@.some size' cannot match: 'arg1 size'.
> Does not match with:
> insideABlock: arg1 part2: arg2
> |temp1 temp3|
> [arg1 size].
> temp1 := arg2 + 3.
> ^arg2
Then even if you remove the extra dots, the rule won't match the method you
give.
This is because this method has no statements matching '``@some size' (even if
it has a block that has a statement that can).
So here is a rule that can match your method:
`a: `aa `b: `bb
| `@temps |
`@.stms1.
[ `@rcv size ].
`@.stms2.
> After looking while I realize that is not matching with
> part1: arg1 part2: arg2
> |temp1 temp2 temp3|
> arg1 size.
> temp1 := arg2 + 3.
> ^arg2
This one however can be matched by your rule (without the extra dots).
I think that you should try to parse expressions instead of full methods
(RBParseTreeSearcher>>#matches:do: instead of
RBParseTreeSearcher>>#matchesMethod:do:).
You could just try to match '`@rcv size': it would succeed in both methods.
>
> Until I understand:
> ``@.some size ``@.more.
> This should mean: anything that sends the message size, doesn't matter if we
> have something before or after, I think that this expression should match
> both cases.
>
> But maybe I'm missunderstanding the patterns (again).
It should work like that (modulo bugs)
` denotes a metavariable
adding @ means you're looking for a list of elements
ex: `receiver `@msg: `@arg matches every message
adding a . means you're looking for a statement (or a list of statement if you
combine it with @)
adding # means you're looking for a literal
adding another ` means that the pattern will be searched recursively in each
subexpressions even if the top one already matched
it sometimes leads to infinite loops, but I don't remember exactly when
ex: in 'foo bar bar' :
if you search for '`rcv bar' you'll find one match ('foo bar bar')
if you search for '``rcv bar' you'll find two matches ('foo bar' and 'foo bar
bar').
and I think it's all
>
> Any help with this will be really welcome!
>
>
