tiny typo (apache#709)

Author: pmcgee69

docs/custom_sql_parser.md

@@ -4,7 +4,7 @@ I have explored many different ways of building this library to make it easy to
 
 The concept is simply to write a new parser that delegates to the ANSI parser so that as much as possible of the core functionality can be re-used.
 
-I also plan on building in specific support for custom data types, where a lambda function can be parsed to the parser to parse data types.
+I also plan on building in specific support for custom data types, where a lambda function can be passed to the parser to parse data types.
 
 For an example of this, see the [DataFusion](https://github.com/apache/arrow-datafusion) project and its [query planner] (https://github.com/apache/arrow-datafusion/tree/master/datafusion/sql).