Reynold Xin 9914b1b2c5 [SPARK-9150][SQL] Create CodegenFallback and Unevaluable trait ... It is very hard to track which expressions have code gen implemented or not. This patch removes the default fallback gencode implementation from Expression, and moves that into a new trait called CodegenFallback. Each concrete expression needs to either implement code generation, or mix in CodegenFallback. This makes it very easy to track which expressions have code generation implemented already. Additionally, this patch creates an Unevaluable trait that can be used to track expressions that don't support evaluation (e.g. Star). Author: Reynold Xin <rxin@databricks.com> Closes #7487 from rxin/codegenfallback and squashes the following commits: 14ebf38 [Reynold Xin] Fixed Conv 6c1c882 [Reynold Xin] Fixed Alias. b42611b [Reynold Xin] [SPARK-9150][SQL] Create a trait to track code generation for expressions. cb5c066 [Reynold Xin] Removed extra import. 39cbe40 [Reynold Xin] [SPARK-8240][SQL] string function: concat		2015-07-18 18:18:19 -07:00
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src	[SPARK-9150][SQL] Create CodegenFallback and Unevaluable trait	2015-07-18 18:18:19 -07:00
pom.xml	[SPARK-9015] [BUILD] Clean project import in scala ide	2015-07-16 18:42:41 +01:00