What is the pretaproot module for

[tcharding]

The pretaproot module, and specifically the PreTaprootDescriptor type, contains duplicate code from the Descrpitor type. It is not immediately obvious what this module is for?

Would adding this method to Descriptor enable users of the library to check a descriptor before using it if they specifically needed a pre-taproot descriptor?

    /// Returns true if this desciptor represents scripts from _before_ Taproot was enabled.
    pub fn is_pre_taproot(&self) -> bool {
        use Descriptor::*;

        match self {
            Bare(_) | Pkh(_) | Wpkh(_) | Sh(_) | Wsh(_) => true,
            Tr(_) => false,
        }
    }

[apoelstra]

@tcharding there are several different methods in PreTaprootDescriptor vs Descriptor. In particular things that did not return a ``Result` pre-Taproot now do.

[tcharding]

oooo, I missed that. Thanks.