IntlChar::isIDStart
PHP function
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(PHP 7, PHP 8)
Check if code point is permissible as the first character in an identifier
Description
IntlChar::isIDStart(int|string $codepoint): bool|null
Determines if the specified character is permissible as the first character in an identifier according to Unicode (The Unicode Standard, Version 3.0, chapter 5.16 Identifiers).
true for characters with general categories "L" (letters) and "Nl" (letter numbers).
Parameters
codepointParameter
Return Values
Returns true if codepoint may start an identifier, false if not. Returns null on failure.
Examples
Example
php
<?php
var_dump(IntlChar::isIDStart("A"));
var_dump(IntlChar::isIDStart("$"));
var_dump(IntlChar::isIDStart("\n"));
var_dump(IntlChar::isIDStart("\u{2603}"));
?>The above example will output:
output
bool(true)
bool(false)
bool(false)
bool(false)See Also
IntlChar::isalpha()IntlChar::isIDPart()IntlChar::PROPERTY_ID_START