Is your feature request related to a use case or problem? Please explain
This is a limited-scope follow-up to #7908 - the PR which initially intended to enhance QASM parser with a support for parameterized gates.
Describe the solution you would prefer
OpenQASM3 allows parameterized gates with the input modifier. Here is a minimum example that imports as parameterized circuit in Qiskit:
qasm = "OPENQASM 3.0; qreg q[1]; input float[64] phi; U(phi, 0, 0) q[0];"
circuit = qiskit.qasm3.loads(q1)
It would be nice to have it working in Cirq too and produce gates with appropriately named symbolic parameter(s):
from cirq.contrib.qasm_import import circuit_from_qasm
circuit = circuit_from_qasm(qasm) # fails
The QasmParser needs to learn float, angle, and input keywords as appropriate for QASM3 vs QASM2 language versions. This should be done with a minimum intrusion to the QasmParser code and with care to keep, if possible, existing API interfaces unchanged.
How urgent is this for you? Is it blocking important work?
P3 – I'm not really blocked by it; it's an idea I'm proposing based on principle
PS: I am not sure how much need is there for this feature. The priority can be increased if we get upvotes here.
Is your feature request related to a use case or problem? Please explain
This is a limited-scope follow-up to #7908 - the PR which initially intended to enhance QASM parser with a support for parameterized gates.
Describe the solution you would prefer
OpenQASM3 allows parameterized gates with the
inputmodifier. Here is a minimum example that imports as parameterized circuit in Qiskit:It would be nice to have it working in Cirq too and produce gates with appropriately named symbolic parameter(s):
The QasmParser needs to learn
float,angle, andinputkeywords as appropriate for QASM3 vs QASM2 language versions. This should be done with a minimum intrusion to the QasmParser code and with care to keep, if possible, existing API interfaces unchanged.How urgent is this for you? Is it blocking important work?
P3 – I'm not really blocked by it; it's an idea I'm proposing based on principle
PS: I am not sure how much need is there for this feature. The priority can be increased if we get upvotes here.