> On 09.02.2018, at 19:06, Fabio Niephaus <lists@fniephaus.com> wrote:
>
> On Fri, Feb 9, 2018 at 6:31 PM Chris Cunningham <cunningham.cb@gmail.com> wrote:
> #xor: is on the same plane as #| and #& - evaluate both sides and apply
>
> We also have #and: and #or: - evaluate receiver, and evaluate argument block if and only if necessary.
>
> I use #and: and #or: for speed purposes - and to avoid side effects (sometimes).
>
> I'm just curious - is there an equivalent symbol for xor similar to | and & that we could use?
>
> In some languages, they use ^ but for obvious reason that's not useful. I wonder if we could use ~ for #xor:?

Wikipedia says:

"It is symbolized by the prefix operator J[2] and by the infix operators XOR (/ˌɛks ˈɔːr/), EOR, EXOR, ⊻, ⩒, ⩛, ⊕, ↮, and ≢. "

Theoretically, we could use any of these symbols, (⊕ is often used in maths) but our fonts don't display them yet, so that has to wait.

Further there:

        "+, a plus sign", well, would work (on booleans) but could be confusing
        "J, as in Jpq", not working for us

        ", sometimes written as
        • ><
        • >-<"

        THAT could work.

I like

        a >< b

it looks like an X a bit.

Best regards
        -Tobias



PS: GMail/Inbox apparently destroys the citation level :(

>
>
> Also, before making this change to using blocks (if we do), we'd need to fix all users - probably also in the VMMaker packages.
>
> Right...fortunately, there aren't that many senders...
>
> Fabio
>
>
> -cbc
>
> On Fri, Feb 9, 2018 at 9:18 AM, Levente Uzonyi <leves@caesar.elte.hu> wrote:
> On Fri, 9 Feb 2018, marcel.taeumel wrote:
>
> commits-2 wrote
> A new version of Kernel was added to project The Inbox:
> http://source.squeak.org/inbox/Kernel-fn.1151.mcz
>
> ==================== Summary ====================
>
> Name: Kernel-fn.1151
> Author: fn
> Time: 9 February 2018, 12:32:25.516883 pm
> UUID: 9fb7df4b-6bf4-4af8-9c75-7496c2f0b517
> Ancestors: Kernel-tonyg.1150
>
> For consistency: allow blocks to be passed into #xor: (see #or: and
> #and:).
>
> =============== Diff against Kernel-tonyg.1150 ===============
>
> Item was changed:
>  ----- Method: False>>xor: (in category 'logical operations') -----
> + xor: alternativeBlock
> - xor: aBoolean
>        "Posted by Eliot Miranda to squeak-dev on 3/24/2009"
>
> +       ^alternativeBlock value!
> -       ^aBoolean!
>
> Item was changed:
>  ----- Method: True>>xor: (in category 'logical operations') -----
> + xor: alternativeBlock
> - xor: aBoolean
>        "Posted by Eliot Miranda to squeak-dev on 3/24/2009"
>
> +       ^alternativeBlock value not!
> -       ^aBoolean not!
>
> Hey Nicolas,
>
> it seems that you had the intention to not allow "a xor: [b]" because,
> obviously, one does always have to check both operands for XOR. Yet, would
> it do any harm if we would allow "a xor: [b]"?
>
> Performance. Two fold: you create a block for no reason, because it will always be evaluated right after its creation.
> If there is no block, #value still has to be sent.
>
> Levente
>
>
>
> Best,
> Marcel
>
>
>
> --
> Sent from: http://forum.world.st/Squeak-Dev-f45488.html
>
>
>
>