To compare strings case-insensitively, you want case-folding instead of lowercase or uppercase. Unicode defines case-folding for comparing strings. There are en

To compare strings case-insensitively, you want case-folding instead of lowercase or uppercase. Unicode defines case-folding for comparing strings. There are enough complexities with case, like characters that don't have other case or multiple mappings, that it can't be correctly used for comparison.