Any chance of adding a boolean exclusive or? Like ^^?
It's a thing that too many programming languages lack, in my opinion.

/ Ola Frid

Ola Frid <olafrid atyay dtek.chalmers otday se> wrote:
> Any chance of adding a boolean exclusive or? Like ^^?
> It's a thing that too many programming languages lack, in my opinion.

Fewer than you think!

We usually call it !=

:)

 -- andy

In article <cein8f$21i8$1@digitaldaemon.com>, Ola Frid <olafrid atyay dtek.chalmers otday se> says...
>
>Any chance of adding a boolean exclusive or? Like ^^?
>It's a thing that too many programming languages lack, in my opinion.
>
>/ Ola Frid

In D, as has been much discussed in the past, a boolean value is just a int (bah!), with the type "bool" aliased to "bit".

Therefore, the operator ^ will do what you want.

# bool b = (x == y) ^ (z > 0);

Arcane Jill

In article <cej0hj$258c$1@digitaldaemon.com>, Arcane Jill says...
>
>In article <cein8f$21i8$1@digitaldaemon.com>, Ola Frid <olafrid atyay dtek.chalmers otday se> says...
>>
>>Any chance of adding a boolean exclusive or? Like ^^?
>>It's a thing that too many programming languages lack, in my opinion.
>>
>>/ Ola Frid
>
>In D, as has been much discussed in the past, a boolean value is just a int (bah!), with the type "bool" aliased to "bit".
>
>Therefore, the operator ^ will do what you want.
>
># bool b = (x == y) ^ (z > 0);
>
>Arcane Jill
>
>

Wha..what!? In D a "bit" is a "int"? But...isn't it a waste to use 32 bits when
there could be used only 8? (that is, using a (0, !0) "byte" for boolean values)

Lord Syl wrote:
> 
> Wha..what!? In D a "bit" is a "int"? But...isn't it a waste to use 32 bits when
> there could be used only 8? (that is, using a (0, !0) "byte" for boolean values)

In D, a bit is stored in one byte and arrays of bits are packed so they actually are one bit in size.


Sean

Lord Syl wrote:
> In article <cej0hj$258c$1@digitaldaemon.com>, Arcane Jill says...
> 
>>In article <cein8f$21i8$1@digitaldaemon.com>, Ola Frid <olafrid atyay
>>dtek.chalmers otday se> says...
>>
>>>Any chance of adding a boolean exclusive or? Like ^^?
>>>It's a thing that too many programming languages lack, in my opinion.
>>>
>>>/ Ola Frid
>>
>>In D, as has been much discussed in the past, a boolean value is just a int
>>(bah!), with the type "bool" aliased to "bit".
>>
>>Therefore, the operator ^ will do what you want.
>>
>># bool b = (x == y) ^ (z > 0);
>>
>>Arcane Jill
>>
>>
> 
> 
> Wha..what!? In D a "bit" is a "int"? But...isn't it a waste to use 32 bits when
> there could be used only 8? (that is, using a (0, !0) "byte" for boolean values)
> 
> 
Have you ever looked at the implementations of other languages?
On the other side. You can't easily pack some bits together. Then you would have to do some more asm operations to access it.
We live on 32bit machines today...

Stephan Wienczny

Andy Friesen wrote:

> Ola Frid <olafrid atyay dtek.chalmers otday se> wrote:
> 
>> Any chance of adding a boolean exclusive or? Like ^^?
>> It's a thing that too many programming languages lack, in my opinion.
> 
> 
> Fewer than you think!
> 
> We usually call it !=
> 
> :)
> 
>  -- andy

lol well put...

On Sun, 01 Aug 2004 07:47:23 -0700, Andy Friesen wrote:

> Ola Frid <olafrid atyay dtek.chalmers otday se> wrote:
>> Any chance of adding a boolean exclusive or? Like ^^?
>> It's a thing that too many programming languages lack, in my opinion.
> 
> Fewer than you think!
> 
> We usually call it !=
> 
> :)
> 
>   -- andy

But that only works if you're actually comparing booleans, so something like:

a.opEquals(b) != c.opEquals(d)
isn't necessarily the same as
(a.opEquals(b) == true) != (c.opEquals(d))
whereas since ^^ is a boolean comparison,
a.opEquals(b) ^^ c.opEquals(d)
should compare the same.

Yes?

On Sun, 01 Aug 2004 12:55:55 -0400, teqDruid wrote:

> On Sun, 01 Aug 2004 07:47:23 -0700, Andy Friesen wrote:
> 
>> Ola Frid <olafrid atyay dtek.chalmers otday se> wrote:
>>> Any chance of adding a boolean exclusive or? Like ^^?
>>> It's a thing that too many programming languages lack, in my opinion.
>> 
>> Fewer than you think!
>> 
>> We usually call it !=
>> 
>> :)
>> 
>>   -- andy
> 
> But that only works if you're actually comparing booleans, so something like:
> 
> a.opEquals(b) != c.opEquals(d)
> isn't necessarily the same as
> (a.opEquals(b) == true) != (c.opEquals(d))
oops! amend that to (a.opEquals(b) == true) != (c.opEquals(d) == true)

> whereas since ^^ is a boolean comparison,
> a.opEquals(b) ^^ c.opEquals(d)
> should compare the same.
> 
> Yes?

teqDruid wrote:

> On Sun, 01 Aug 2004 07:47:23 -0700, Andy Friesen wrote:
> 
> 
>>Ola Frid <olafrid atyay dtek.chalmers otday se> wrote:
>>
>>>Any chance of adding a boolean exclusive or? Like ^^?
>>>It's a thing that too many programming languages lack, in my opinion.
>>
>>Fewer than you think!
>>
>>We usually call it !=
>>
>>:)
>>
>>  -- andy
> 
> 
> But that only works if you're actually comparing booleans, so something
> like:
> 
> a.opEquals(b) != c.opEquals(d)
> isn't necessarily the same as
> (a.opEquals(b) == true) != (c.opEquals(d) == true) // <- amended
> whereas since ^^ is a boolean comparison,
> a.opEquals(b) ^^ c.opEquals(d)
> should compare the same.
> 

Only if you create a class and overload the opEquals operator and return a byte/ubyte/int/uint/long/ulong instead of type bit.
Of course you can also overload the opEquals with return type Object...

Sadlly the compiler does not seem to be consistent about not being able to convert an int to a bit.