GT attribute expressions with different data types

[maxkratz]

Currently, it is not possible to either:

• compare, e.g., an ELong variable with an EInt
• compare said ELong variable with an ELong constant.

In my example, substrateNode.residualCpu is an ELong and I want to check if it is greater than 0:

Possible feature requests:

1. Implement a language feature to express (E)Longs in GT rules/patterns, e.g.: # substrateNode.residualCpu > 0l
2. Implement a feature for the backend, that compatible data types can be "casted" automatically. This would allow comparing, e.g., ELongs with EInts: # substrateNode.residualCpu > 0

IMO is 2. the preferred solution as this is how it is handled in Java.