docs: update docs & changelog

CHANGELOG.md

@@ -28,16 +28,18 @@ See [Conventional Commits](Https://conventionalcommits.org) for commit guideline
 * the semantics of `forbid_unless` were not wrong
 
 ## [v2.0.0-rc.1](https://github.com/ash-project/ash/compare/v2.0.0-rc.0...v2.0.0-rc.1) (2022-09-04)
-
-
-
-
 ### Bug Fixes:
 
 * `forbid_unless` expression compilation
 
 * fix runtime filter join simulation for multiple rows
 
+## [v2.0.0-rc.0](https://github.com/ash-project/ash/compare/v1.53.3...v2.0.0-rc.0) (2022-09-04)
+
+### Bug Fixes:
+
+* Initial Ash 2.0.0-rc.0 release!
+
 ## [v1.53.3](https://github.com/ash-project/ash/compare/v1.53.2...v1.53.3) (2022-08-22)
 
 

documentation/how_to/upgrade.md

@@ -18,6 +18,7 @@ These should all be straight forward enough to do a simple find and replace in y
 - `source_field_on_join_table` -> `source_attribute_on_join_resource`
 - `destination_field_on_join_table` -> `destination_attribute_on_join_resource`
 - `no_fields?` -> `no_attributes?`
+- `expensive?` -> `before_action?` (on validations)
 
 ### DSL changes
 

documentation/topics/expressions.md

@@ -40,6 +40,7 @@ The following functions are built in:
 - `get_path` | i.e `get_path(value, ["foo", "bar"])`. This is what expressions like `value[:foo]["bar"]` are turned into under the hood.
 - `ago` | i.e `deleted_at > ago(7, :day)`. The available time intervals are documented in {{link:ash:module:Ash.Type.DurationName}}
 - `contains` | if one string contains another string, i.e `contains("fred", "red")`
+- `exists` | `exists(foo.bar, name == "fred")` takes an expression scoped to the destination, and 
 
 ## Primitives
 
@@ -48,16 +49,16 @@ The following functions are built in:
 
 ## Templates
 
-Most of the time, when you are using an expression, you will actually be creating a `template`. In this template, you have a few references that can be used, which will be replaced when before the expression is evaluated. The following references are available:
+Most of the time, when you are using an expression, you will actually be creating a `template`. In this template, you have a few references that can be used, which will be replaced when before the expression is evaluated. The following references are available. The ones that start with `^` must be imported from `Ash.Filter.TemplateHelpers`.
 
 ```elixir
-actor(:key) # equivalent to `get_in(actor || %{}, [:key])`
-actor([:key1, :key2]) # equivalent to `get_in(actor || %{}, [:key, :key2])`
-arg(:arg_name) # equivalent to `Map.get(arguments, :arg_name)`
+^actor(:key) # equivalent to `get_in(actor || %{}, [:key])`
+^actor([:key1, :key2]) # equivalent to `get_in(actor || %{}, [:key, :key2])`
+^arg(:arg_name) # equivalent to `Map.get(arguments, :arg_name)`
+^context(:key) # equivalent to `get_in(context, :key)`
+^context([:key1, :key2]) # equivalent to `get_in(context, [:key1, :key2])`
 ref(:key) # equivalent to referring to `key`. Allows for dynamic references
 ref(:key, [:path]) # equivalent to referring to `path.key`. Allows for dynamic references with dynamic (or static) paths.
-context(:key) # equivalent to `get_in(context, :key)`
-context([:key1, :key2]) # equivalent to `get_in(context, [:key1, :key2])`
 ```
 
 ## Use cases for expressions