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digitalmars.D - The bit type...

reply Sam <Sam_member pathlink.com> writes:
I read an argument about the 'bit' type.  It seems people can do this:

int i = true * 8; // yields 8
i = false * 8; // yields 0 ?

Static operators or methods eliminate this problem!  Get rid of the 'true' and
'false' keywords!!

I propose:

bit a;
bit.settrue(a);
bit b;
bit.setfalse(b);
a = b || !b;

There are probably better names for these 2 methods...  'setto1' and 'setto0'?
Doing so eliminates the need for 'true' and 'false' keywords!

I would like to see the following keywords ELIMINATED, as they are just a source
for exceptions:

null
false
true

Sam-
sam987883 yahoo.com
May 26 2005
next sibling parent reply "Unknown W. Brackets" <unknown simplemachines.org> writes:
If that happened, I would add this to all my fales:

const int true = 1;
const int false = 0;
const void* null = cast(void*) 0;

Remember - bit and bool are the same type.  You're asking me to change this:

bool test()
{
    return true;
}

To this:

bool test()
{
    bool tempvar;
    tempvar.setto1();
    return tempvar;
}


JavaScript, etc.) all have concepts of true and false.

-[Unknown]



 I read an argument about the 'bit' type.  It seems people can do this:
 
 int i = true * 8; // yields 8
 i = false * 8; // yields 0 ?
 
 Static operators or methods eliminate this problem!  Get rid of the 'true' and
 'false' keywords!!
 
 I propose:
 
 bit a;
 bit.settrue(a);
 bit b;
 bit.setfalse(b);
 a = b || !b;
 
 There are probably better names for these 2 methods...  'setto1' and 'setto0'?
 Doing so eliminates the need for 'true' and 'false' keywords!
May 26 2005
parent Sam <Sam_member pathlink.com> writes:
In that case, you could do:

bool test()
{
return 1; // (bool) 1
}

'true' and 'false' are specific interpretations of 'bool' or 'bit', not
applicable to all situations!  'on' or 'off', 'enabled' or 'disabled', etc.

So it should be up to the developer to always define their own constants:

const int true = 1;
const int false = 0;
const int on = 1;
const int off = 0;
const int enabled = 1;
const int disabled = 0;

See?

If you don't like my 'truthify' and 'falsify' methods, then let's stick to 0 or
1 and the = operator.

In article <d7528c$2rpn$1 digitaldaemon.com>, Unknown W. Brackets says...

If that happened, I would add this to all my fales:

const int true = 1;
const int false = 0;
const void* null = cast(void*) 0;

Remember - bit and bool are the same type.  You're asking me to change this:

bool test()
{
    return true;
}

To this:

bool test()
{
    bool tempvar;
    tempvar.setto1();
    return tempvar;
}


JavaScript, etc.) all have concepts of true and false.

-[Unknown]



 I read an argument about the 'bit' type.  It seems people can do this:
 
 int i = true * 8; // yields 8
 i = false * 8; // yields 0 ?
 
 Static operators or methods eliminate this problem!  Get rid of the 'true' and
 'false' keywords!!
 
 I propose:
 
 bit a;
 bit.settrue(a);
 bit b;
 bit.setfalse(b);
 a = b || !b;
 
 There are probably better names for these 2 methods...  'setto1' and 'setto0'?
 Doing so eliminates the need for 'true' and 'false' keywords!
May 26 2005
prev sibling next sibling parent Nick <Nick_member pathlink.com> writes:
In article <d751eu$2r8p$1 digitaldaemon.com>, Sam says...

I propose:

bit a;
bit.settrue(a);
bit b;
bit.setfalse(b);
a = b || !b;

 [...]
I would like to see the following keywords ELIMINATED, as they are just a
 source for exceptions:

null
false
true


You really like setter functions and hate keywords don't you ;-) But I honestly
can't say I understand why the current syntax (with keywords) is a problem.

Nick
May 26 2005
prev sibling next sibling parent reply "Jim H" <jimh nowhere.com> writes:
I could see an argument for making true and false distinct from integer 



But getting rid of true and false altogether....I don't know about that. Why 
do you say they cause exceptions?

Jim


"Sam" <Sam_member pathlink.com> wrote in message 
news:d751eu$2r8p$1 digitaldaemon.com...

 I read an argument about the 'bit' type.  It seems people can do this:

 int i = true * 8; // yields 8
 i = false * 8; // yields 0 ?

 Static operators or methods eliminate this problem!  Get rid of the 'true' 
 and
 'false' keywords!!

 I propose:

 bit a;
 bit.settrue(a);
 bit b;
 bit.setfalse(b);
 a = b || !b;

 There are probably better names for these 2 methods...  'setto1' and 
 'setto0'?
 Doing so eliminates the need for 'true' and 'false' keywords!

 I would like to see the following keywords ELIMINATED, as they are just a 
 source
 for exceptions:

 null
 false
 true

 Sam-
 sam987883 yahoo.com
May 26 2005
parent reply Sam <Sam_member pathlink.com> writes:


I don't mean to sound like a Boolean extremist, but how often do these 2
keywords get used??  Honestly????

Basically, true and false have only 2 functions, and you only ever need only one
of them!!!  Because false = !true

One function is testing a value:

if(b == true)

BUT, you can just do this:

if(b)

Second is assignment:

b = true;
b = !true;

BUT, you can do this instead:

b = 1;
b = 0;

1 and 0 are already part of almost every programming language!

Why keep keywords that are not needed?


In C++ we didn't have a 'null' keyword, and we never needed one!

The less keywords a language has, the simpler it bacomes and the easier it is to
learn.

Exceptions from true and false??  Maybe!  What does this do:

cout << true << false; // ?

In article <d756vq$307c$1 digitaldaemon.com>, Jim H says...

I could see an argument for making true and false distinct from integer 



But getting rid of true and false altogether....I don't know about that. Why 
do you say they cause exceptions?

Jim


"Sam" <Sam_member pathlink.com> wrote in message 
news:d751eu$2r8p$1 digitaldaemon.com...

 I read an argument about the 'bit' type.  It seems people can do this:

 int i = true * 8; // yields 8
 i = false * 8; // yields 0 ?

 Static operators or methods eliminate this problem!  Get rid of the 'true' 
 and
 'false' keywords!!

 I propose:

 bit a;
 bit.settrue(a);
 bit b;
 bit.setfalse(b);
 a = b || !b;

 There are probably better names for these 2 methods...  'setto1' and 
 'setto0'?
 Doing so eliminates the need for 'true' and 'false' keywords!

 I would like to see the following keywords ELIMINATED, as they are just a 
 source
 for exceptions:

 null
 false
 true

 Sam-
 sam987883 yahoo.com
May 26 2005
next sibling parent Derek Parnell <derek psych.ward> writes:
On Thu, 26 May 2005 20:23:16 +0000 (UTC), Sam wrote:



'false'!
 
 I don't mean to sound like a Boolean extremist, but how often do these 2
 keywords get used??  Honestly????


In my Build utility I use these key words 185 times.


 Basically, true and false have only 2 functions, and you only ever need only
one
 of them!!!  Because false = !true


So let's also write all numeric literals in binary too, 'cos we only need
ones and zeros to do that.
 

 One function is testing a value:
 
 if(b == true)
 
 BUT, you can just do this:
 
 if(b)
 
 Second is assignment:
 
 b = true;
 b = !true;
 
 BUT, you can do this instead:
 
 b = 1;
 b = 0;
 
 1 and 0 are already part of almost every programming language!
 
 Why keep keywords that are not needed?


To make code easier for people to read. A programming language's main
purpose is to help people to express algorithms in a cost-effective manner.
To be able to easily write and read programming code is paramount.


 In C++ we didn't have a 'null' keyword, and we never needed one!
 
 The less keywords a language has, the simpler it bacomes and the easier it is
to
 learn.


Have you ever had a good look at Forth? Now that is a language with a small
(read: non-existent) set of keywords. 

-- 
Derek Parnell
Melbourne, Australia
27/05/2005 6:26:51 AM
May 26 2005
prev sibling next sibling parent reply "Jim H" <jimh nowhere.com> writes:
Well, Sam, I think you have used up your allotment of exclamation points for 
the whole week!! :-)


"Sam" <Sam_member pathlink.com> wrote in message 
news:d75b7k$2a6$1 digitaldaemon.com...

 BUT, you can just do this:

 if(b)


But what does this really mean? If 'b' is what?

The if statement works on a boolean expression. The implied meaning is "if b 
!= 0". And that meaning is built into the language and you have to know 
that. Boolean false is 0 and boolean true is anything not 0. At least in C 
that's the case. (But in some other language maybe not.)

So as Mr Brackets pointed out, people will start to define "true" and 
"false" in their code all the time. As in:

  const int true = 1;
  const int false = 0;

or perhaps...

   enum bool {false, true}

It can help to add something to the language that everyone uses a lot 
anyway; see the rationale for builtins in D.

A problem is that one person will define "true=1", someone else will define 
"TRUE=1", and a third person will define "True=1". It gets confusing.

One thing that popped into mind is: what if I meant to type:

if(b == 42)        // evaluates to a boolean
{}

but I accidentally typed:

if(b = 42)         // evaluates to an integer
{}

I'm sure there are better examples but that's all I can think of at the 
moment.


 Second is assignment:

 b = true;
 b = !true;

 BUT, you can do this instead:

 b = 1;
 b = 0;

 1 and 0 are already part of almost every programming language!

 Why keep keywords that are not needed?


It may be _possible_ to do that. But to me, "true" is conceptually a 
different thing than "1". And I think it's clearer if the code reflects that 
difference. A boolean is more like an enumeration that has two values, true 
and false, and cannot be set to anything else.


 In C++ we didn't have a 'null' keyword, and we never needed one!

 The less keywords a language has, the simpler it bacomes and the easier it 
 is to
 learn.


But EVERYONE always defines NULL = 0 anyway. And then there's all that 
casting since 0 isn't really a pointer type.


 Exceptions from true and false??  Maybe!  What does this do:

 cout << true << false; // ?


On Microsoft C++ it outputs a 1 and then a 0. I don't know about any other 
implementations or languages.

Jim
May 26 2005
parent reply Sam <Sam_member pathlink.com> writes:
Yeah, you're probably right!  Yeah, I do use too many exclamation points!
Elaine from Seinfeld would not be pleased!

I like you argument of people always defining their own constants, and making it
part of the language keeps them consistent.

I got burned once a looooooooooong time ago...   In a company far, far away...

It was the end of the Clinton era, and the job market was booming...

I did something like:

std::cout << true;

Except it wasn't with STL...  I don't remember if it was with VB6, MFC or java,
but one of those languages screwed me my outputing to a file the string "true"
and "false", INSTEAD of 1 or 0.

Like most people I never test my code (that's extra time I could be using to
write more code or surfing the web) and I got burned!  Bad!!

Wish I could remember which language this was in...


In article <d75h5o$7f3$1 digitaldaemon.com>, Jim H says...

Well, Sam, I think you have used up your allotment of exclamation points for 
the whole week!! :-)


"Sam" <Sam_member pathlink.com> wrote in message 
news:d75b7k$2a6$1 digitaldaemon.com...

 BUT, you can just do this:

 if(b)


But what does this really mean? If 'b' is what?

The if statement works on a boolean expression. The implied meaning is "if b 
!= 0". And that meaning is built into the language and you have to know 
that. Boolean false is 0 and boolean true is anything not 0. At least in C 
that's the case. (But in some other language maybe not.)

So as Mr Brackets pointed out, people will start to define "true" and 
"false" in their code all the time. As in:

  const int true = 1;
  const int false = 0;

or perhaps...

   enum bool {false, true}

It can help to add something to the language that everyone uses a lot 
anyway; see the rationale for builtins in D.

A problem is that one person will define "true=1", someone else will define 
"TRUE=1", and a third person will define "True=1". It gets confusing.

One thing that popped into mind is: what if I meant to type:

if(b == 42)        // evaluates to a boolean
{}

but I accidentally typed:

if(b = 42)         // evaluates to an integer
{}

I'm sure there are better examples but that's all I can think of at the 
moment.


 Second is assignment:

 b = true;
 b = !true;

 BUT, you can do this instead:

 b = 1;
 b = 0;

 1 and 0 are already part of almost every programming language!

 Why keep keywords that are not needed?


It may be _possible_ to do that. But to me, "true" is conceptually a 
different thing than "1". And I think it's clearer if the code reflects that 
difference. A boolean is more like an enumeration that has two values, true 
and false, and cannot be set to anything else.


 In C++ we didn't have a 'null' keyword, and we never needed one!

 The less keywords a language has, the simpler it bacomes and the easier it 
 is to
 learn.


But EVERYONE always defines NULL = 0 anyway. And then there's all that 
casting since 0 isn't really a pointer type.


 Exceptions from true and false??  Maybe!  What does this do:

 cout << true << false; // ?


On Microsoft C++ it outputs a 1 and then a 0. I don't know about any other 
implementations or languages.

Jim
May 26 2005
next sibling parent reply "Jarrett Billingsley" <kb3ctd2 yahoo.com> writes:
"Sam" <Sam_member pathlink.com> wrote in message 
news:d75itd$8nt$1 digitaldaemon.com...

 Except it wasn't with STL...  I don't remember if it was with VB6, MFC or 
 java,
 but one of those languages screwed me my outputing to a file the string 
 "true"
 and "false", INSTEAD of 1 or 0.
 Wish I could remember which language this was in...


MFC is not a language, and std::cout << true; is quite obviously C++ code..


 Like most people I never test my code


You mean _unlike_ most people?

Something tells me you're not a programmer by trade.  That, or you aren't a 
very good one.
May 26 2005
next sibling parent "Unknown W. Brackets" <unknown simplemachines.org> writes:
Come, come... let's not go insulting.  Everyone's friends here :).  As 
they say in various other places - let's attack *positions* not *people*.

Anyway, I wouldn't ever do this:

writef(true);

Because its effect is undefined in my mind; sure, I would expect 1, but 
it doesn't make logical sense.  I would do this, instead:

writef(cast(int) true);

Or much more likely:

writef(true ? "1" : "0");

-[Unknown]



 "Sam" <Sam_member pathlink.com> wrote in message 
 news:d75itd$8nt$1 digitaldaemon.com...
 

Except it wasn't with STL...  I don't remember if it was with VB6, MFC or 
java,
but one of those languages screwed me my outputing to a file the string 
"true"
and "false", INSTEAD of 1 or 0.
Wish I could remember which language this was in...


 
 
 MFC is not a language, and std::cout << true; is quite obviously C++ code..
 
 

Like most people I never test my code


 
 
 You mean _unlike_ most people?
 
 Something tells me you're not a programmer by trade.  That, or you aren't a 
 very good one.
May 26 2005
prev sibling parent Kyle Furlong <ky220 umail.ucsb.edu> writes:
 Something tells me you're not a programmer by trade.  That, or you aren't a 
 very good one. 


Indeed.
May 27 2005
prev sibling parent Matthias Becker <Matthias_member pathlink.com> writes:
I did something like:

std::cout << true;

Except it wasn't with STL...  I don't remember if it was with VB6, MFC or java,
but one of those languages screwed me my outputing to a file the string "true"
and "false", INSTEAD of 1 or 0.


The iostram isn't part of the STL!

And you got that output in that language/library because true and false have the
type bool/boolean/... and not int/integer/... . If you want to write a 0 or a 1
than just do that. Don't expect the language to do some mistirious things if you
aren't absolutly sure it will.

BTW, ever used std::boolalpha ?


Like most people I never test my code (that's extra time I could be using to
write more code or surfing the web) and I got burned!  Bad!!


LOL! You never test your code? Yre you sure you've ever written a program that
actually works?
May 27 2005
prev sibling next sibling parent Matthias Becker <Matthias_member pathlink.com> writes:


I don't mean to sound like a Boolean extremist, but how often do these 2
keywords get used??  Honestly????


I can only speek for myself, but I use them often.


Basically, true and false have only 2 functions, and you only ever need only one
of them!!!  Because false = !true


right and 2 = 1+1 so let's get rid of all literals beside 0 and 1. Perhaps we
should remove 0 as well, as it can be expressed as 1-1.


One function is testing a value:

if(b == true)

BUT, you can just do this:

if(b)

Second is assignment:

b = true;
b = !true;

BUT, you can do this instead:

b = 1;
b = 0;

1 and 0 are already part of almost every programming language!

Why keep keywords that are not needed?


Instead of 





you can write





so why should we keep those stupid keywords like while and do? Or look at this:






So we can remove for as well.


In C++ we didn't have a 'null' keyword, and we never needed one!


It will get one, but it's called nullptr.







The less keywords a language has, the simpler it bacomes and the easier it is to
learn.


Nope. A language with more keywords is often much easier. E.g. D has a foreach
keyword which often makes iteration much simpler than in C++.



Exceptions from true and false??  Maybe!  What does this do:

cout << true << false; // ?


How often have you written this code? If you aren't sure what your code does,
don't write it. You could use




to get sure.

-- Matthias Becker
May 27 2005
prev sibling parent Hasan Aljudy <hasan.aljudy gmail.com> writes:
Sam wrote:


'false'!
 
 I don't mean to sound like a Boolean extremist, but how often do these 2
 keywords get used??  Honestly????


Any half decent programmer would use them ALOT.
I Do.

btw, it's really scary that you don't test your code.


 Basically, true and false have only 2 functions, and you only ever need only
one
 of them!!!  Because false = !true
 
 One function is testing a value:
 
 if(b == true)


Dude .. this is one of the most important functions in programming: 
without it, there wouldn't be any programs.


 BUT, you can just do this:
 
 if(b)


That's because at the low level, booleans are simply a test against zero.
But that's at the low level.
The purpose of programming languages is to bring programming to higher 
levels.


 Second is assignment:
 
 b = true;
 b = !true;
 
 BUT, you can do this instead:
 
 b = 1;
 b = 0;


you can also write
char b[] = "Hello world"
as
char b[] = { 72, 101, 108, 108, 111, 32, 87, 111, 114, 108, 100 }

except that the first is logically sound, while the second is 
meaningless to humans.
Both are the same to computers, though.


 In C++ we didn't have a 'null' keyword, and we never needed one!


we actually do ... as has been mentioned before
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2004/n1601.pdf
May 27 2005
prev sibling next sibling parent zwang <nehzgnaw gmail.com> writes:
Sam wrote:

 I read an argument about the 'bit' type.  It seems people can do this:
 
 int i = true * 8; // yields 8
 i = false * 8; // yields 0 ?


If people are doing this, they must have good reasons.
I don't think these keywords are causing any problems here.
Besides, your proposed method is truly a verbose eyesore to me.


 
 Static operators or methods eliminate this problem!  Get rid of the 'true' and
 'false' keywords!!
 
 I propose:
 
 bit a;
 bit.settrue(a);
 bit b;
 bit.setfalse(b);
 a = b || !b;
 
 There are probably better names for these 2 methods...  'setto1' and 'setto0'?
 Doing so eliminates the need for 'true' and 'false' keywords!
 
 I would like to see the following keywords ELIMINATED, as they are just a
source
 for exceptions:
 
 null
 false
 true
 
 Sam-
 sam987883 yahoo.com
May 26 2005
prev sibling parent Matthias Becker <Matthias_member pathlink.com> writes:
I read an argument about the 'bit' type.  It seems people can do this:

int i = true * 8; // yields 8
i = false * 8; // yields 0 ?


Why should anybody ever write code like this? The only reason I can see is an
obfuscation-contest.


Static operators or methods eliminate this problem!  Get rid of the 'true' and
'false' keywords!!

I propose:

bit a;
bit.settrue(a);
bit b;
bit.setfalse(b);
a = b || !b;

There are probably better names for these 2 methods...  'setto1' and 'setto0'?
Doing so eliminates the need for 'true' and 'false' keywords!


and you can read your code above much faster than:
May 27 2005