(PHP 7)
IntlChar::isalpha — Check if code point is a letter character
Determines whether the specified code point is a letter character. TRUE for general categories "L" (letters).
Returns TRUE if
codepoint is a letter character, FALSE if not.
Exemplo #1 Testando codepoints diferentes
<?php
var_dump(IntlChar::isalpha("A"));
var_dump(IntlChar::isalpha("1"));
var_dump(IntlChar::isalpha("\u{2603}"));
?>
O exemplo acima irá imprimir:
bool(true) bool(false) bool(false)