Argument assignment in execution fucntion throws an error

[zohimchandani]

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Describe the bug

import cudaq

@cudaq.kernel
def bit_flip(which_m: int):
    
    qubits = cudaq.qvector(1)
            
    #create psi
    u3(1,2,3, qubits[0])
    
    if which_m == 1:
        mz(qubits[0])
 
#this works since argument is defined outside of sample and passed in         
which_m = 1
counts = cudaq.sample(bit_flip, which_m, shots_count = 1)

#this throws an error when argument is defined  within sample 
counts = cudaq.sample(bit_flip, which_m=1, shots_count = 1)

Steps to reproduce the bug

NA

Expected behavior

NA

Is this a regression? If it is, put the last known working version (or commit) here.

Not a regression

Environment

• CUDA-Q version:
• Python version:
• C++ compiler:
• Operating system:

Suggestions

No response

[bmhowe23]

I think this is consistent with how Python handles other functions that take both positional and keyword arguments like cudaq.sample. For example, the following fails with an error message.

def custom_func(a, b, c=0):
    print(f"a={a}, b={b}, c={c}")

custom_func(1, which_m = 2, c=3)

But if you use the walrus operator (:=), you can fix this:

def custom_func(a, b, c=0):
    print(f"a={a}, b={b}, c={c}")

custom_func(1, which_m:=2, c=3)

Similarly, you can use which_m:=1 in your case.

Let me know if that works for you.