Adding a statement when rewriting

rewriter := RBParseTreeRewriter new
                replace: 'attributes := OrderedCollection new.'
                with: 'attributes := Set new'.
        tree := ConfigurationTemplate parseTreeFor: #customProjectAttributes.
        rewriter executeTree: tree.
returns true, but:
        rewriter := RBParseTreeRewriter new
                replace: 'attributes := OrderedCollection new.'
                with: 'attributes := Set new. self halt'.
        tree := ConfigurationTemplate parseTreeFor: #customProjectAttributes.
        rewriter executeTree: tree.
returns false.

Why does adding a statement cause this rewrite to fail and how should I bet doing it?

Thanks,
Sean

On Feb 9, 2013, at 9:19 PM, Sean P. DeNigris <[hidden email]> wrote:

I'm puzzle too.
I started to write a chapter on the rewrtie engine to force me to look at it but I got distracted.

stephane ducasse wrote

I'm puzzle too.

Thanks for taking a look. I got it to work by matching the source of the whole method like this:
'| `@Temps |
attributes := OrderedCollection new.
(condition) ifTrue: [ attributes add: #zinc ] "My new statement here".
``@.Statements.'.

My naive guess is that if you try to modify more than a single node, you must operate on the next biggest node...

stephane ducasse wrote

I started to write a chapter on the rewrtie engine to force me to look at it but I got distracted.

I found http://www.refactory.com/the-rewritetool which is a good starting point...