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<?php $x = 'yo'; for( $i = 0; $i <= 3; $i++ ) { echo "substr( '$x', $i ) is: ", var_export(substr( $x, $i ),true), "\n"; } echo "\n\n"; $x = ''; echo "substr( '$x', 0 ) is: ", var_export(substr( $x, 0 ),true), "\n"; echo "substr( '$x', 1 ) is: ", var_export(substr( $x, 1 ),true), "\n";
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 42) Position 1 = 17
Branch analysis from position: 17
2 jumps found. (Code = 44) Position 1 = 19, Position 2 = 3
Branch analysis from position: 19
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 3
2 jumps found. (Code = 44) Position 1 = 19, Position 2 = 3
Branch analysis from position: 19
Branch analysis from position: 3
filename:       /in/AspGv
function name:  (null)
number of ops:  44
compiled vars:  !0 = $x, !1 = $i
line      #* E I O op                               fetch          ext  return  operands
-----------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                       !0, 'yo'
    4     1        ASSIGN                                                       !1, 0
          2      > JMP                                                          ->17
    5     3    >   ROPE_INIT                                         5  ~5      'substr%28+%27'
          4        ROPE_ADD                                          1  ~5      ~5, !0
          5        ROPE_ADD                                          2  ~5      ~5, '%27%2C+'
          6        ROPE_ADD                                          3  ~5      ~5, !1
          7        ROPE_END                                          4  ~4      ~5, '+%29+is%3A+'
          8        ECHO                                                         ~4
          9        INIT_FCALL                                                   'var_export'
         10        FRAMELESS_ICALL_2                substr              ~8      !0, !1
         11        SEND_VAL                                                     ~8
         12        SEND_VAL                                                     <true>
         13        DO_ICALL                                             $9      
         14        ECHO                                                         $9
         15        ECHO                                                         '%0A'
    4    16        PRE_INC                                                      !1
         17    >   IS_SMALLER_OR_EQUAL                                          !1, 3
         18      > JMPNZ                                                        ~11, ->3
    8    19    >   ECHO                                                         '%0A%0A'
   10    20        ASSIGN                                                       !0, ''
   11    21        ROPE_INIT                                         3  ~14     'substr%28+%27'
         22        ROPE_ADD                                          1  ~14     ~14, !0
         23        ROPE_END                                          2  ~13     ~14, '%27%2C+0+%29+is%3A+'
         24        ECHO                                                         ~13
         25        INIT_FCALL                                                   'var_export'
         26        FRAMELESS_ICALL_2                substr              ~16     !0, 0
         27        SEND_VAL                                                     ~16
         28        SEND_VAL                                                     <true>
         29        DO_ICALL                                             $17     
         30        ECHO                                                         $17
         31        ECHO                                                         '%0A'
   12    32        ROPE_INIT                                         3  ~19     'substr%28+%27'
         33        ROPE_ADD                                          1  ~19     ~19, !0
         34        ROPE_END                                          2  ~18     ~19, '%27%2C+1+%29+is%3A+'
         35        ECHO                                                         ~18
         36        INIT_FCALL                                                   'var_export'
         37        FRAMELESS_ICALL_2                substr              ~21     !0, 1
         38        SEND_VAL                                                     ~21
         39        SEND_VAL                                                     <true>
         40        DO_ICALL                                             $22     
         41        ECHO                                                         $22
         42        ECHO                                                         '%0A'
         43      > RETURN                                                       1

Generated using Vulcan Logic Dumper, using php 8.5.0


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