I have a numpy structured array and pass one element in it to a function as below.

@njit
def process(a):
    # some work
    a[0]      # works
    i = 0
    a[i]     # works
    a[i+1]   # does not work

I can confirm that a is indeed a Record, instead of sth else like an array etc. It seems like indexing is only allowed by a constant, which can be an integer or a CharSeq, known at compile time, but not an expresson on the constant, which is also known at compile time though. May I know what is happening under the hood?

I have tried other constant as index like “j=i; a[j]”, which also works. But unsurprisingly “j=i+1;a[j]” fails.