Trie implementation of Norvig's spellchecker based on this discussion. Performance test is in example directory, on my laptop (Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz) get following results
> julia norvigs.jl
0.748 of 270 correct (0.056 unknown) at 5382.885 words per second
0.426627 seconds (1.21 M allocations: 52.142 MiB, 7.34% gc time)
0.675 of 400 correct (0.108 unknown) at 3664.988 words per second
0.109498 seconds (475.77 k allocations: 14.612 MiB, 33.29% gc time)
Benchmark testset1, average speed: 5929.07 words per second
Benchmark testset2, average speed: 5665.096 words per second