Thinking about it again, the code is in set-variable.
Look for :match there.
Thanks for checking and replying.
No, I don't see that, however. That code is about checking that a given
value is of the right type.
I want to compare two types themselves, to see if they are compatible (one
is <= the other). I don't want to check the type of a value.
I want to know if the custom types defined for two variables are compatible:
whether the type defined for var1 is compatible with the type defined for
var2. If the type of var1 is `regexp' and the type of var2 is `string', for
example, then the types are compatible (var1's type <= var2's type) -
regardless of the current values. Testing current values is not sufficient.
It's really what I said before:
Given a custom type, how can I find all user options that
have that type (or a compatible type, such as a subtype)?
By "have that type", I meant "are defined with that type", not "have values
of that type".