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<?php $haystack = 'foobar'; $needle = 'foo'; var_dump(substr($haystack, 0, strlen($needle)) === $needle);
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/6jsjf
function name:  (null)
number of ops:  13
compiled vars:  !0 = $haystack, !1 = $needle
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, 'foobar'
    5     1        ASSIGN                                                   !1, 'foo'
    7     2        INIT_FCALL                                               'var_dump'
          3        INIT_FCALL                                               'substr'
          4        SEND_VAR                                                 !0
          5        SEND_VAL                                                 0
          6        STRLEN                                           ~4      !1
          7        SEND_VAL                                                 ~4
          8        DO_ICALL                                         $5      
          9        IS_IDENTICAL                                     ~6      !1, $5
         10        SEND_VAL                                                 ~6
         11        DO_ICALL                                                 
         12      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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