Bug: Measurement after swap and cx

[cjn10]

The following code yields an error

a = QuantumFloat(2)
swap(a[0], a[1])
cx(a[0], a[1])
multi_measurement([a])
>> AttributeError: 'int' object has no attribute 'identifier'

The same happens when using a.get_measurement. This appears to be a problem with the swap and cx gate together with the measurement. Removing any of the three operations avoids the error.

[positr0nium]

Hi, at least currently the multi_measurement feature is only intended to measure multiple quantum variables not multiple qubits. We could change that. In any case we should set up an error message that checks the type.

[renezander90]

But it seems to be a compiler bug:

from qrisp import *

a = QuantumFloat(2)
swap(a[0], a[1])
cx(a[0], a[1])
a.qs.compile()

Yields:
AttributeError: 'int' object has no attribute 'identifier'

[cjn10]

The bug appeared once I merged the main branch into #205, see e9948c6.

[positr0nium]

Fixed in f28594b.