The problem is that you are making the language ambiguous. To get your desired behavior you probably need the lexical analyzer less eager. That’s a hard thing to do, because you probably need to adjust its behavior based on the syntactic context - whether the parser thinks that it is parsing the name of a type.
Every java parser has to solve the same problem, so you should see how they solve it. I question whether we want SQL to look like Java. This includes whether we use < and > for parameterized types, and whether we include every possible operator such as >> and &&. Julian > On Oct 12, 2023, at 02:13, Hongyu Guo <guohongyu...@gmail.com> wrote: > > Hi devs, > > I want to add some new bitwise operators to Babel parser, specifically the > left shift "<<" and the right shift ">>". > > To do this, I add `"< BITWISE_RIGHT_SHIFT: \">>\" >"` > to binaryOperatorsTokens in babel/src/main/codegen/config.fmpp and a new > SqlBinaryOperator to > core/src/main/java/org/apache/calcite/sql/fun/SqlLibraryOperators.java, > similar to what was done in CALCITE-4980[1]. > > But I have noticed this change causes an error when using SQL like `select > cast(a as map<varchar multiset, map<int, int>>)`. This is because the SQL > contains `>>` string, I want to know how to avoid this awkward error. > Thanks. > > [1] https://issues.apache.org/jira/browse/CALCITE-4980 > > Best, > hongyu guo
