Specs

upcase(t(), :default | :ascii | :greek | :turkic) :: t()

Converts all characters in the given string to uppercase according to mode.

mode may be :default, :ascii, :greek or :turkic. The :default mode considers all non-conditional transformations outlined in the Unicode standard. :ascii uppercases only the letters a to z. :greek includes the context sensitive mappings found in Greek. :turkic properly handles the letter i with the dotless variant.

Examples

iex> String.upcase("abcd")
"ABCD"

iex> String.upcase("ab 123 xpto")
"AB 123 XPTO"

iex> String.upcase("olá")
"OLÁ"

The :ascii mode ignores Unicode characters and provides a more performant implementation when you know the string contains only ASCII characters:

iex> String.upcase("olá", :ascii)
"OLá"

And :turkic properly handles the letter i with the dotless variant:

iex> String.upcase("ıi")
"II"

iex> String.upcase("ıi", :turkic)
"Iİ"