IntlChar::isIDStart
Check if code point is permissible as the first character in an identifier
Description
public static boolnull IntlChar::isIDStart(intstring $codepoint
)
true
for characters with general categories "L" (letters) and "Nl" (letter numbers).
Parameters
-
codepoint
-
The int codepoint value (e.g. 0x2603
for U+2603 SNOWMAN), or the character encoded as a UTF-8 string (e.g. "\u{2603}"
)
Return Values
Returns true
if
codepoint
may start an identifier, false
if not. Returns null
on failure.
Examples
Example #1 Testing different code points
<?php
var_dump(IntlChar::isIDStart("A"));
var_dump(IntlChar::isIDStart("$"));
var_dump(IntlChar::isIDStart("\n"));
var_dump(IntlChar::isIDStart("\u{2603}"));
?>
The above example will output:
bool(true)
bool(false)
bool(false)
bool(false)
See Also
- IntlChar::isalpha
- IntlChar::isIDPart
IntlChar::PROPERTY_ID_START