pch-012.md

New feature of double-quoted string's complex-curly syntax in PHP >= 5.5

@cywm528 date:2014-03-02

I found a new feature of double-quoted string's complex-curly syntax in PHP >= 5.5 zend_language_scanner.l in PHP <= 5.4：

<ST_LOOKING_FOR_VARNAME>{LABEL} {
	zend_copy_value(zendlval, yytext, yyleng);
	zendlval->type = IS_STRING;
	yy_pop_state(TSRMLS_C);
	yy_push_state(ST_IN_SCRIPTING TSRMLS_CC);
	return T_STRING_VARNAME;
}

zend_language_scanner.l in PHP >= 5.5：

<ST_LOOKING_FOR_VARNAME>{LABEL}[[}] {
	yyless(yyleng - 1);
	zend_copy_value(zendlval, yytext, yyleng);
	zendlval->type = IS_STRING;
	yy_pop_state(TSRMLS_C);
	yy_push_state(ST_IN_SCRIPTING TSRMLS_CC);
	return T_STRING_VARNAME;
}

Well, php code can be evaluated in double-quoted string, like this:

// PHP >= 4.3, and maybe older varsion?
"{${phpinfo()}}";
"{$phpinfo[phpinfo()]}";
"${${phpinfo()}}";
"${@phpinfo()}";
"${ phpinfo()}";
"${( string )phpinfo()}";
"${phpinfo[phpinfo()]}";

// this is new feature in PHP >= 5.5
"${phpinfo()}";