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IntlChar::isIDStart

(PHP 7)

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

Description

代码语言:javascript
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public static bool IntlChar::isIDStart ( mixed $codepoint )

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 integer 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

代码语言:javascript
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<?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:

代码语言:javascript
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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

← IntlChar::isIDPart

IntlChar::isISOControl →

代码语言:txt
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 ? 1997–2017 The PHP Documentation Group

Licensed under the Creative Commons Attribution License v3.0 or later.

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