This document specifies <tt>combo()</tt> output script descriptors.
These take a key and produce P2PK, P2PKH, P2WPKH, and P2SH-P2WPKH output scripts if applicable to the key.
==Copyright==
This BIP is licensed under the BSD 2-clause license.
==Motivation==
In order to make the transition from traditional key based wallets to descriptor based wallets easier, it is useful to be able to take a key and produce the scripts which have traditionally been produced by wallet software.
==Specification==
A new top level script expression is defined: <tt>combo(KEY)</tt>.
This expression can only be used as a top level expression.
It takes a single key expression as an argument and produces either 2 or 4 output scripts, depending on the key.
A <tt>combo()</tt> expression always produces a P2PK and P2PKH script, the same as putting the key in both a <tt>pk()</tt> and a <tt>pkh()</tt> expression.
If the key is/has a compressed public key, then P2WPKH and P2SH-P2WPKH scripts are also produced, the same as putting the key in both a <tt>wpkh()</tt> and <tt>sh(wpkh())</tt> expression.
Valid descriptors followed by the scripts they produce. Descriptors involving derived child keys will have the 0th, and 1st scripts in additional sub-bullets.
