Hi, I'm using Apache Calcite to run some SQL transformations on Apache sparks SQL statements. I would like to extract the type signature out of spark.catalog.listFunctions to be able to register them in Calcite with their proper signature.
>From the API, I can get the fully qualified class name and the name, but unfortunately, the type signature is not present. Would there be a way to use reflection to extract? For example: https://github.com/apache/spark/blob/master/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/stringExpressions.scala#L424 Ideally, it would be convenient to get the type signature from org.apache.spark.sql.catalog.Function itself when available. -- Guillaume Massé [Gee-OHM] (马赛卫)
