decompose() new parameters provide decompose multiple time, or till the end

What should we add?

example:
circuit.decompose().decompose().decompose().decompose().decompose()

can be something like:

circuit.decompose(reps = 5) # repeat decompose 5 times

why: I found it useful when decompose initialize state, and see how gate change each decompose

• repeat decompose #8142
• repeat gates_to_decompose

[jakelishman]

I explained in the other PR - I don’t see a need for any modification to gates_to_decompose here, and I think adding it would confuse the interface of a generally simple function. I’ll close the re-opened part of this issue (as it’s effectively a feature request) as “won’t fix”, but thanks for the initial PR!

[jakelishman]

This seems both easy to implement and a simple shorthand for people. In general, decompose isn’t the best way of translating between basis gates (the BasisTranslator transpiler pass is our preferrred method now), but I do know people still use decompose as a quick check.

I’d be happy to accept a PR on this that adds reps as the keyword argument in QuantumCircuit.decompose - it just needs to loop over the call to the Decomposer pass that many times.