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Function std.ascii.toUpper

Converts an ASCII letter to uppercase.

auto toUpper(C) (
  C c
if (is(C : dchar));


c Any type which implicitly converts to dchar. In the case where it's a built-in type, or an enum of a built-in type, Unqual!(OriginalType!C) is returned, whereas if it's a user-defined type, dchar is returned.


The corresponding uppercase letter, if c is a lowercase ASCII character, otherwise c itself.


writeln(toUpper('a')); // 'A'
writeln(toUpper('A')); // 'A'
writeln(toUpper('#')); // '#'

// N.B.: Non-ASCII Unicode lowercase letters are not converted.
writeln(toUpper('á')); // 'á'


Walter Bright and Jonathan M Davis


Boost License 1.0.