slamdata/slamengine — pull request #72 by mossprescott (2014-06-24 20:53:10+00:00)
Title: nicer errors for Pipeline phase

This just makes it easier to debug errors in the Pipeline phase. For example:

```
[info] x plan filter with between
[error] 'Left(Function RANGE cannot be compiled to a pipeline op
[error] func: RANGE
[error] args:
[error] Int(10)
[error] selector: None
[error] expr: Some(Literal(Int64(10)))
[error] pipeline: \/-(None)
[error] Int(100)
[error] selector: None
[error] expr: Some(Literal(Int64(100)))
[error] pipeline: \/-(None)
[error] java.lang.Thread.getStackTrace(Thread.java:1551)
[error] slamdata.engine.Error$class.$init$(errors.scala:10)
[error] slamdata.engine.PlannerError$InternalError.(errors.scala:106)
[error] slamdata.engine.physical.mongodb.MongoDbPlanner$.slamdata$engine$physical$mongodb$MongoDbPlanner$$funcError$1(p```