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<?php class zyf{ public $a=6; public $b; function zyf(){ echo $this->a; //可以输出 6 如果替换为echo $a ,将不显示任何结果,因为没有具体对象 } } $xin = new zyf(); ?>
Finding entry points
Branch analysis from position: 0
Jump found. Position 1 = -2
filename:       /in/7VAbN
function name:  (null)
number of ops:  5
compiled vars:  !0 = $xin
line     #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
   2     0  E >   NOP                                                      
   9     1        NEW                                              $2      :-6
         2        DO_FCALL                                      0          
         3        ASSIGN                                                   !0, $2
         4      > RETURN                                                   1

Class zyf:
Function zyf:
Finding entry points
Branch analysis from position: 0
Jump found. Position 1 = -2
filename:       /in/7VAbN
function name:  zyf
number of ops:  3
compiled vars:  none
line     #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
   6     0  E >   FETCH_OBJ_R                                      $0      'a'
         1        ECHO                                                     $0
   7     2      > RETURN                                                   null

End of function zyf

End of class zyf.

Generated using Vulcan Logic Dumper, using php 7.2.0