Flex: xor

[RSAAdmin]

There is no builtin function in Flex to perform an xor.  However, you can still perform an xor (it's just tedious).

The following Flex snippet xor's two 1-byte values (varA and varB) into a third (varXor).  This builds on my earlier post "Flex: if-else logic".  It could be extended to xor values up to 8 bytes (flex supports number-type variables up to 64 bits).

<assign name="varXor" value="0"/>

<assign name="checkA" value="0"/>

<assign name="checkB" value="0"/>
<if name="varA" and="1">

     <assign name="checkA" value="1"/>

     <if name="varB" and="1">

          <assign name="checkB" value="1"/>
     </if>

     <if name="checkB" equal="0">

          <or name="varXor" value="1"/>

     </if>

</if>

<if name="checkA" equal="0">

     <if name="varB" and="1">

          <or name="varXor" value="1"/>

     </if>

</if>

<assign name="checkA" value="0"/>

<assign name="checkB" value="0"/>

<if name="varA" and="2">

     <assign name="checkA" value="1"/>

     <if name="varB" and="2">

          <assign name="checkB" value="1"/>

     </if>

     <if name="checkB" equal="0">

          <or name="varXor" value="2"/>

     </if>

</if>

<if name="checkA" equal="0">

     <if name="varB" and="2">

          <or name="varXor" value="2"/>

     </if>

</if>

<assign name="checkA" value="0"/>

<assign name="checkB" value="0"/>

<if name="varA" and="4">

     <assign name="checkA" value="1"/>

     <if name="varB" and="4">

          <assign name="checkB" value="1"/>

     </if>

     <if name="checkB" equal="0">

          <or name="varXor" value="4"/>

     </if>

</if>

<if name="checkA" equal="0">

     <if name="varB" and="4">

          <or name="varXor" value="4"/>

     </if>

</if>

<assign name="checkA" value="0"/>

<assign name="checkB" value="0"/>

<if name="varA" and="8">

     <assign name="checkA" value="1"/>

     <if name="varB" and="8">

          <assign name="checkB" value="1"/>

     </if>

     <if name="checkB" equal="0">

          <or name="varXor" value="8"/>

     </if>

</if>

<if name="checkA" equal="0">

     <if name="varB" and="8">

          <or name="varXor" value="8"/>

     </if>

</if>

<assign name="checkA" value="0"/>

<assign name="checkB" value="0"/>

<if name="varA" and="16">

     <assign name="checkA" value="1"/>

     <if name="varB" and="16">

          <assign name="checkB" value="1"/>

     </if>

     <if name="checkB" equal="0">

          <or name="varXor" value="16"/>

     </if>

</if>

<if name="checkA" equal="0">

     <if name="varB" and="16">

          <or name="varXor" value="16"/>

     </if>

</if>

<assign name="checkA" value="0"/>

<assign name="checkB" value="0"/>

<if name="varA" and="32">

     <assign name="checkA" value="1"/>

     <if name="varB" and="32">

          <assign name="checkB" value="1"/>

     </if>

     <if name="checkB" equal="0">

          <or name="varXor" value="32"/>

     </if>

</if>

<if name="checkA" equal="0">

     <if name="varB" and="32">

          <or name="varXor" value="32"/>

     </if>

</if>

<assign name="checkA" value="0"/>

<assign name="checkB" value="0"/>

<if name="varA" and="64">

     <assign name="checkA" value="1"/>

     <if name="varB" and="64">

          <assign name="checkB" value="1"/>

     </if>

     <if name="checkB" equal="0">

          <or name="varXor" value="64"/>

     </if>

</if>

<if name="checkA" equal="0">

     <if name="varB" and="64">

          <or name="varXor" value="64"/>

     </if>

</if>

<assign name="checkA" value="0"/>

<assign name="checkB" value="0"/>

<if name="varA" and="128">

     <assign name="checkA" value="1"/>

     <if name="varB" and="128">

          <assign name="checkB" value="1"/>

     </if>

     <if name="checkB" equal="0">

          <or name="varXor" value="128"/>

     </if>

</if>

<if name="checkA" equal="0">

     <if name="varB" and="128">

          <or name="varXor" value="128"/>

     </if>

</if>

[RSAAdmin]

Color me impressed for figuring out how to xor data (up to 8 bytes) in XML.  You never cease to amaze me. +1 vote for a new Ninja level that is only held by you in this forum.

[RSAAdmin]

I second Sconzo's remark. This is exceptional work! This is useful in a number of ways. I'm guessing since you are only using if statements and avoided reads, finds, and such this is rather fast?

[RSAAdmin]

Thanks!

Yeah, it should be fast.  There is a little bit of a performance penalty for each "if".  But you can't really write a parser without them...