Selects upper-case or title-case alphabetic Unicode characters
(letters). Title case is used by a small number of letter ligatures
like the single-character form of
Lj.
Note: this predicate does
not work for letter-like
characters such as:
'Ⓐ' (
U+24B6 circled Latin
capital letter A) and
'Ⅳ' (
U+2163 Roman numeral
four). This is due to selecting only characters with the
GeneralCategory UppercaseLetter or
TitlecaseLetter.
See
isUpperCase for a more intuitive predicate. Note that
unlike
isUpperCase,
isUpper does select
title-case characters such as
'Dž' (
U+01C5
Latin capital letter d with small letter z with caron) or
'ᾯ'
(
U+1FAF Greek capital letter omega with dasia and perispomeni
and prosgegrammeni).