* wip type transforming serializers
* old python sucks
* typing fixups
* Expose the `to` parameter on `rx.serializer` for type conversion
Serializers can also return a tuple of `(serialized_value, type)`, if both ways
are specified, then the returned value MUST match the `to` parameter.
When initializing a new rx.Var, if `_var_is_string` is not specified and the serializer returns a `str` type, then mark `_var_is_string=True` to indicate that the Var should be treated like a string literal.
Include datetime, color, types, and paths as "serializing to str" type.
Avoid other changes at this point to reduce fallout from this change:
Notably, the `serialize_str` function does NOT cast to `str`, which
would cause existing code to treat all Var initialized with a str as a
str literal even though this was NOT the default before.
Update test cases to accomodate these changes.
* Raise deprecation warning for rx.Var.create with string literal
In the future, we will treat strings as string literals in the JS code. To get
a Var that is not treated like a string, pass _var_is_string=False.
This will allow our serializers to automatically identify cast string literals
with less special cases (and the special cases need to be explicitly
identified).
* Add test case for mismatched serialized types
* fix old python
* Remove serializer returning a tuple feature
Simplify the logic; instead of making a wrapper function that returns
a tuple, just save the type conversions in a separate global.
* Reset the LRU cache when adding new serializers
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Co-authored-by: Masen Furer <m_github@0x26.net>