for the SQL standard LATERAL keyword, currently only supported
by Postgresql.  fixes #2857

INSERT, UPDATE, and DELETE statements to both specify their own
WITH clause, as well as for these statements themselves to be
CTE expressions when they include a RETURNING clause.
fixes #2551

expression element which is late-evaluated at compile time.  Previously,
the function was only a conversion function which would handle different
expression inputs by returning either a :class:`.Label` of a column-oriented
expression or a copy of a given :class:`.BindParameter` object,
which in particular prevented the operation from being logically
maintained when an ORM-level expression transformation would convert
a column to a bound parameter (e.g. for lazy loading).
fixes #3531

``<function> WITHIN GROUP (ORDER BY <criteria>)``, using the
method :class:`.FunctionElement.within_group`.  A series of common
set-aggregate functions with return types derived from the set have
been added. This includes functions like :class:`.percentile_cont`,
:class:`.dense_rank` and others.
fixes #1370
- make sure we use func.name for all _literal_as_binds in functions.py
so we get consistent naming behavior for parameters.

- any/all work for Array as well as subqueries, accepted by MySQL
- Postgresql ARRAY now subclasses Array
- fixes #3516

- attempt to add a script to semi-automate the fixing of links

of the "constants" :func:`.null`, :func:`.true`, and :func:`.false`
has been reverted.   These functions returning a "singleton" object
had the effect that different instances would be treated as the
same regardless of lexical use, which in particular would impact
the rendering of the columns clause of a SELECT statement.
fixes #3170