php 语法分析格式的有关问题-关于bison action的有关问题

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|	T_FOR<br />
		'('<br />
			for_expr<br />
		';' { zend_do_free(&$3 TSRMLS_CC); $4.u.op.opline_num = get_next_op_number(CG(active_op_array)); }<br />
			for_expr<br />
		';' { zend_do_extended_info(TSRMLS_C); zend_do_for_cond(&$6, &$7 TSRMLS_CC); }<br />
			for_expr<br />
		')' { zend_do_free(&$9 TSRMLS_CC); zend_do_for_before_statement(&$4, &$7 TSRMLS_CC); }<br />
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';' { zend_do_free(&$3 TSRMLS_CC); $4.u.op.opline_num = get_next_op_number(CG(active_op_array)); }<br />