<?php
for ( |dd0000|$i = 0|; |00dd00|$i < 42|; |0000dd|++$i| ) {
    |dd00dd|echo $i;|
}

        |dd0000|init: AST_EXPR_LIST|
            0: AST_ASSIGN
                var: AST_VAR
                    name: "i"
                expr: 0
        |00dd00|cond: AST_EXPR_LIST|
            0: AST_BINARY_OP
                flags: BINARY_IS_SMALLER (19)
                left: AST_VAR
                    name: "i"
                right: 42
        |0000dd|loop: AST_EXPR_LIST|
            0: AST_PRE_INC
                var: AST_VAR
                    name: "i"
        |dd00dd|stmts: …|
compiled vars:  !0 = $i
line     #* E I O op                           fetch          ext  return  operands
   2     0  E >   EXT_STMT                                                 
         1        |dd0000|ASSIGN                                                   !0, 0|
         2      > |dd0000|JMP                                                      ->6|
   4     3    >   |dd00dd|EXT_STMT                                                 |
         4        |dd00dd|ECHO                                                     !0|
   2     5        |0000dd|PRE_INC                                                  !0|
         6    >   |00dd00|IS_SMALLER                                       ~3      !0, 42|
         7        |00dd00|EXT_STMT                                                 |
         8      > |00dd00|JMPNZ                                                    ~3, ->3|
         9    > > RETURN                                                   1