Always refer to backreferences , not octal codes 總是指反向引用,而不是八進(jìn)制代碼。
And up are considered backreferences if there is a backreference corresponding to that number ; otherwise , they are interpreted as octal codes unless the starting digits are 8 or 9 , in which case they are treated as literal " 8 " and " 9 " 和更高位表達(dá)式在具有與該號碼對應(yīng)的反向引用時被視作反向引用;否則,它們會被解釋為八進(jìn)制代碼(除非起始位是8或9 ,在這種情況下它們被視為原義的“ 8 ”和“ 9 ” ) 。