You get this warning because 0 (or the enum equivalent) is not a valid value
for the type `RNA` and `newSeq` elements are initialized to 0. In the case of
`map` the warning is wrong since the elements are properly initialized but the
compiler couldn't follow the control flow.
Example:
proc test =
var x = newSeq[range[1..1]](5)
Run
You can add `--warning[ProveInit]:off` to your `nim.cfg` or add `{.push
warning[ProveInit]: off.}` to your file.
Unrelated tip: If a table is constant and the keys are contiguous, you can just
use an array to avoid hashing/lookups.
const
tblDNAtoRNA = [T: RNA U, A: A, G: G, C: C]
proc transcribe(n: DNA): RNA =
tblDNAtoRNA[n]
Run
