feature request: use different value validators selected by key validators

[jremmet]

Usecase: a dict with keys where the name shows which kind of validator should be used to validate it.
e.g.

{
    "val_foo": 1
    "val_bar": 2
    "str_foo: "hello"
    "str_bar": "world"
}

To validate this directly something like this would be nice:

Dict(extra=[
    (Str(pattern="val_.*"), Int()),
    (Str(pattern = "str_.*), Str())
])

I didn't find a way to avoid link the key and value validator. Splitting this up via OneOf fails if both kinds of keys are present.

[kr41]

Good point! However, I would like to implement more general solution.