d

```
-- Computes the Hamming "edit" distance for two strings of the same length:
-- The number of indices at which the corresponding bytes are different.
return function(
a, -- some string
b -- other string
)
assert(#a == #b, "lengths don't match")
local dist = 0
for i = 1, #a do
if a:byte(i) ~= b:byte(i) then
dist = dist + 1
end
end
return dist
end
```