IntlChar::isIDStart

(PHP 7, PHP 8)

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

Descrizione

public static IntlChar::isIDStart(int|string $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).

Elenco dei parametri

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}")

Valori restituiti

Returns true if codepoint may start an identifier, false if not. Returns null on failure.

Esempi

Example #1 Testing different code points

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

Il precedente esempio visualizzerà:

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

Vedere anche:

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

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