Single-codepoint uppercase mapping for c. Falls back to c for characters with no mapping and for codepoints above U+10FFFF.

For characters whose Unicode uppercase form expands to multiple codepoints (e.g. ß → SS, fi → FI), this returns only the first codepoint of the expansion. Use hasUppercaseExpansion(c:) to detect the multi-char case and uppercaseExpansion(c:) to retrieve the full String.

Examples

toUppercase('a') // 'A' toUppercase('ß') // 'S' — see uppercaseExpansion for "SS" toUppercase('1') // '1' — no mapping