Handle compile-time evaluation correctly

[GoogleCodeExporter]

Every parser should have a compile-time context that is used during
compile-time evaluation. Also, all compile-time evaluation should go
through a single point in the code so that we can augment it when necessary. 

Original issue reported on code.google.com by Rainer.G...@gmx.de on 9 Oct 2009 at 1:42

[GoogleCodeExporter]

Proposed solution: Add an eval(Expr) method to the (compile-time) environment, 
which
in turn has access to a compile-time context stored in that environment. 

To enable access to the compile-time environment, it is stored in the root of 
the
expression tree (a TopExpr like QueryExpr or ExplainExpr). Expr will get a
compileTimeEval() method which (per default) evaluates the expression using the
environment stored at the root of the tree. 

Original comment by Rainer.G...@gmx.de on 9 Oct 2009 at 10:57

[GoogleCodeExporter]

Fixed in r386

Original comment by Rainer.G...@gmx.de on 13 Oct 2009 at 5:27

• Changed state: Fixed