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<?php $a = []; $b = array_merge([4 => 1], $a); var_dump($b); $a = []; $b = [4 => 1] + $a; var_dump($b);
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/42i4k
function name:  (null)
number of ops:  16
compiled vars:  !0 = $a, !1 = $b
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, <array>
    4     1        INIT_FCALL                                               'array_merge'
          2        SEND_VAL                                                 <array>
          3        SEND_VAR                                                 !0
          4        DO_ICALL                                         $3      
          5        ASSIGN                                                   !1, $3
    6     6        INIT_FCALL                                               'var_dump'
          7        SEND_VAR                                                 !1
          8        DO_ICALL                                                 
    8     9        ASSIGN                                                   !0, <array>
    9    10        ADD                                              ~7      <array>, !0
         11        ASSIGN                                                   !1, ~7
   11    12        INIT_FCALL                                               'var_dump'
         13        SEND_VAR                                                 !1
         14        DO_ICALL                                                 
         15      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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