#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?

Also, before making this change to using blocks (if we do), we'd need to fix all users - probably also in the VMMaker packages.

-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