Php/docs/intlchar.isidstart

• PHP Manual
• IntlChar
• Check if code point is permissible as the first character in an identifier

IntlChar::isIDStart

(PHP 7)

IntlChar::isIDStart — Check if code point is permissible as the first character in an identifier

Description

public static IntlChar::isIDStart ( mixed $codepoint ) : bool

Determines if the specified character is permissible as the first character in an identifier according to Unicode (The Unicode Standard, Version 3.0, chapter 5.16 Identifiers).

TRUE for characters with general categories "L" (letters) and "Nl" (letter numbers).

Parameters

codepoint

The int codepoint value (e.g. 0x2603 for U+2603 SNOWMAN), or the character encoded as a UTF-8 string (e.g. "\u{2603}")

Return Values

Returns TRUE if codepoint may start an identifier, FALSE if not.

Examples

Example #1 Testing different code points

<?phpvar_dump(IntlChar::isIDStart("A"));var_dump(IntlChar::isIDStart("$"));var_dump(IntlChar::isIDStart("\n"));var_dump(IntlChar::isIDStart("\u{2603}"));?>

The above example will output:

bool(true)
bool(false)
bool(false)
bool(false)

See Also

• IntlChar::isalpha() - Check if code point is a letter character
• IntlChar::isIDPart() - Check if code point is permissible in an identifier
• IntlChar::PROPERTY_ID_START