Right now we can't express R_i = sum_j A_j as a LambdaGen expression.
We would need a map that operates on vectors of i elements, but has actually no input vectors, and a 0-ary function argument.
Could be implemented this way, without a new primitive (although using a function to return a const value is probably inefficient), but the typechecker has no way to infer the value of i.
Right now we can't express R_i = sum_j A_j as a LambdaGen expression.
We would need a map that operates on vectors of i elements, but has actually no input vectors, and a 0-ary function argument.
Could be implemented this way, without a new primitive (although using a function to return a const value is probably inefficient), but the typechecker has no way to infer the value of i.