* feat: Identifier → VarRef, which represents a tag or field reference
InfluxQL calls these variables, so the Rust parser will follow
precedent.
* chore: Add docs
* chore: Separate arithmetic and conditional expression parsing
This is necessary to ensure conditional expressions are only supported
in a `WHERE` clause and arithmetic expressions in `SELECT` field
projection list
* feat: Add a `verify` API to transform combinator functions to errors
This is useful to preform additional validation on a valid result.
* feat: Add customisation for operand parsing to arithmetic expressions
This permits narrowing of valid function calls in `WHERE` clauses
and to customise valid operands in a `SELECT` projection, such as a
wildcard (`*`)
* chore: move logic to appropriate modules.
* feat: Add wildcard discriminator to Expr enum required for `SELECT`
* chore: Remove dead_code attribute
* feat: Add `DISTINCT` operator
* chore: Add `distinct` macro; simplify existing macros
* chore: add assert_matches; parse Field and Field list; refactor literal
* feat: Add a new type to parse a separated_list1 into a specialised type
* chore: Refactor types using `separated_list1`
* chore: Ensure items in a list can be preceded by a space
* chore: Refactor IN clause to use OneOrMore
* feat: Parse `GROUP BY` clause
* chore: appease clippy
* chore: refactor number parsing to share code; add signed Number type
* feat: completed `SELECT` statement parser.
* chore: Consistent error messages when expecting tokens
* chore: Add recommended derive implementations
* feat: Add `SELECT` statement to `statement` combinator
* chore: Refactor OneOrMore::separated_list1 to a single error message
* chore: More tests and cleanup 🧹
* chore: More tests
* chore: Appease broken doc links checker
* chore: remove remaining `dead_code` attributes 🥳
* chore: Address PR feedback
* https://github.com/influxdata/influxdb_iox/pull/5692#discussion_r982559420
* https://github.com/influxdata/influxdb_iox/pull/5692#discussion_r982527476
* chore: Address PR feedback
* https://github.com/influxdata/influxdb_iox/pull/5692#discussion_r982626857
* https://github.com/influxdata/influxdb_iox/pull/5692#discussion_r982569760
* chore: Address PR feedback for Display implementations
Also removed duplicate test case
Stuart Carnie