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XORs?
f#

I'm trying to implement a (bitwise) xor between two hex strings. I converted them into bytes, and attempted the xor using this approach:

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    let keyBytes = hexStringToBytes(key) in
    let comboBytes = hexStringToBytes(combo) in
    let mutable xorBytes = [||] in
    for i = 0 to keyBytes.Length - 1 do
        let kByte = keyBytes.[i] in
        let cBytes = comboBytes.[i] in
        xorBytes <- Array.append xorBytes (kByte ^^^ cByte);
    done;;

This is part of the same project, with an additional requirement that we didn't know about earlier, so I probably haven't been going about this at all ideally.

Thanks!

.

Ok, I found at least one silly error, in that I neglected to include the array syntax around where I'm actually doing the XOR, if I'm doing it correctly.

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    let keyBytes = hexStringToBytes(key) in
    let comboBytes = hexStringToBytes(combo) in
    let mutable xorBytes = [||] in
    for i = 0 to keyBytes.Length - 1 do
        let kByte = keyBytes.[i] in
        let cByte = comboBytes.[i] in
        xorBytes <- Array.append xorBytes [|(kByte ^^^ cByte)|];
    done;
    let returnBytes = bytesToHexString(xorBytes) in
    returnBytes;;
By on 8/6/2007 10:21 AM ()

You want something like

Array.map2 (^^^) keyBytes comboBytes

- Greg

By on 8/6/2007 8:47 PM ()

Thanks!

By on 8/7/2007 1:53 PM ()

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