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digitalmars.D - Wouldn't it be better if ...

reply Peter <Peter_member pathlink.com> writes:
I was looking at some of the modules such as ctype and math, and see that the
"is" functions (i.e. isalpha, isnan) return a value of type int.  Given that
this is a modern language having boolean types available, would it not be better
to return a value of type boolean?  I'm thinking that code would be clearner.
May 02 2004
next sibling parent reply "Matthew" <matthew.hat stlsoft.dot.org> writes:
Sure would, but we can't agree on what boolean would be!

I think it should be an integral type, whose size is the same as that of the
architecture (for performance; the various supporting reasons for this are in my
<self-serving promotion>forthcoming book "Imperfect C++"</self-serving
promotion>), and which should *not* be implicitly convertible to/from any other
integral type.

But Walter, and a handful of other people, seem content to have it be aliased to
bit.

In the libraries I write, I typedef (remember D's typedefs are strong ones)
boolean from int, and use the casts as appropriate to return them. Walter
doesn't
like this, but I'm immutable on this point.

"Peter" <Peter_member pathlink.com> wrote in message
news:c74i4i$l54$1 digitaldaemon.com...

 I was looking at some of the modules such as ctype and math, and see that the
 "is" functions (i.e. isalpha, isnan) return a value of type int.  Given that
 this is a modern language having boolean types available, would it not be




 to return a value of type boolean?  I'm thinking that code would be clearner.
May 02 2004
next sibling parent J Anderson <REMOVEanderson badmama.com.au> writes:
Matthew wrote:


Sure would, but we can't agree on what boolean would be!

I think it should be an integral type, whose size is the same as that of the
architecture (for performance)
  

But Walter, and a handful of other people, seem content to have it be aliased to
bit.
  



architecture.  I mean for the systems we use now byte is the most 
optimal choice for Boolean (due to caching and other factors).  If your 
using a single bit then it will be the size of a byte.

-- 
-Anderson: http://badmama.com.au/~anderson/
May 02 2004
prev sibling parent reply School <itsnotvalid-news yahoo.com.hk> writes:
Matthew 提到:

 Sure would, but we can't agree on what boolean would be!
 
 I think it should be an integral type, whose size is the same as that of the
 architecture (for performance; the various supporting reasons for this are in
my
 <self-serving promotion>forthcoming book "Imperfect C++"</self-serving
 promotion>), and which should *not* be implicitly convertible to/from any other
 integral type.
 
 But Walter, and a handful of other people, seem content to have it be aliased
to
 bit.
 
 In the libraries I write, I typedef (remember D's typedefs are strong ones)
 boolean from int, and use the casts as appropriate to return them. Walter
doesn't
 like this, but I'm immutable on this point.
 
 "Peter" <Peter_member pathlink.com> wrote in message
 news:c74i4i$l54$1 digitaldaemon.com...
 

I was looking at some of the modules such as ctype and math, and see that the
"is" functions (i.e. isalpha, isnan) return a value of type int.  Given that
this is a modern language having boolean types available, would it not be



 better
 

to return a value of type boolean?  I'm thinking that code would be clearner.






D Programming Language" or "Thinking in D" or "Prefect D".
May 03 2004
parent reply "Matthew" <matthew.hat stlsoft.dot.org> writes:
"School" <itsnotvalid-news yahoo.com.hk> wrote in message
news:c75hcv$23rj$1 digitaldaemon.com...

 Matthew 提到:

 Sure would, but we can't agree on what boolean would be!

 I think it should be an integral type, whose size is the same as that of the
 architecture (for performance; the various supporting reasons for this are in







 <self-serving promotion>forthcoming book "Imperfect C++"</self-serving
 promotion>), and which should *not* be implicitly convertible to/from any







 integral type.

 But Walter, and a handful of other people, seem content to have it be aliased







 bit.

 In the libraries I write, I typedef (remember D's typedefs are strong ones)
 boolean from int, and use the casts as appropriate to return them. Walter







 like this, but I'm immutable on this point.

 "Peter" <Peter_member pathlink.com> wrote in message
 news:c74i4i$l54$1 digitaldaemon.com...


I was looking at some of the modules such as ctype and math, and see that the
"is" functions (i.e. isalpha, isnan) return a value of type int.  Given that
this is a modern language having boolean types available, would it not be



 better


to return a value of type boolean?  I'm thinking that code would be clearner.






 D Programming Language" or "Thinking in D" or "Prefect D".



Well, you may be onto something there. ;)
May 03 2004
parent reply Brad Anderson <brad dsource.dot.org> writes:
http://www.thedprogramminglanguage.com/

Wonder who owns that domain name...

Matthew wrote:

 "School" <itsnotvalid-news yahoo.com.hk> wrote in message
 news:c75hcv$23rj$1 digitaldaemon.com...
 

Matthew 提到:


Sure would, but we can't agree on what boolean would be!

I think it should be an integral type, whose size is the same as that of the
architecture (for performance; the various supporting reasons for this are in






 my
 

<self-serving promotion>forthcoming book "Imperfect C++"</self-serving
promotion>), and which should *not* be implicitly convertible to/from any






 other
 

integral type.

But Walter, and a handful of other people, seem content to have it be aliased






 to
 

bit.

In the libraries I write, I typedef (remember D's typedefs are strong ones)
boolean from int, and use the casts as appropriate to return them. Walter






 doesn't
 

like this, but I'm immutable on this point.

"Peter" <Peter_member pathlink.com> wrote in message
news:c74i4i$l54$1 digitaldaemon.com...



I was looking at some of the modules such as ctype and math, and see that the
"is" functions (i.e. isalpha, isnan) return a value of type int.  Given that
this is a modern language having boolean types available, would it not be



better



to return a value of type boolean?  I'm thinking that code would be clearner.






It would be even better if you write a book called "Learning D" or "The
D Programming Language" or "Thinking in D" or "Prefect D".



 
 Well, you may be onto something there. ;)
May 04 2004
parent reply Stephan Wienczny <wienczny web.de> writes:
If you look at the whois entry, you will see that the owner is Synesis 
Software and the administrative contact is
Dr Matthew D. Wilson

Brad Anderson wrote:

 http://www.thedprogramminglanguage.com/
 
 Wonder who owns that domain name...
May 04 2004
parent Brad Anderson <brad dsource.dot.org> writes:
I'm shocked beyond all reason.  ;)

Stephan Wienczny wrote:

 If you look at the whois entry, you will see that the owner is Synesis 
 Software and the administrative contact is
 Dr Matthew D. Wilson
 
 Brad Anderson wrote:
 

 http://www.thedprogramminglanguage.com/

 Wonder who owns that domain name...
May 04 2004
prev sibling parent reply "Walter" <newshound digitalmars.com> writes:
"Peter" <Peter_member pathlink.com> wrote in message
news:c74i4i$l54$1 digitaldaemon.com...

 I was looking at some of the modules such as ctype and math, and see that




 "is" functions (i.e. isalpha, isnan) return a value of type int.  Given




 this is a modern language having boolean types available, would it not be




 to return a value of type boolean?  I'm thinking that code would be




Generally, a computation of 0 or !0 involves one or two less instructions
than converting it to 0 or 1.
May 02 2004
parent reply Hauke Duden <H.NS.Duden gmx.net> writes:
Walter wrote:

 "Peter" <Peter_member pathlink.com> wrote in message
 news:c74i4i$l54$1 digitaldaemon.com...
 

I was looking at some of the modules such as ctype and math, and see that



 the
 

"is" functions (i.e. isalpha, isnan) return a value of type int.  Given



 that
 

this is a modern language having boolean types available, would it not be



 better
 

to return a value of type boolean?  I'm thinking that code would be



 clearner.
 
 Generally, a computation of 0 or !0 involves one or two less instructions
 than converting it to 0 or 1.
 
 



Well, then maybe a boolean shouldn't be a bit (hint,hint), but its own 
type where true simply means !=0.

IMHO, your using int instead of bool for a situation where you really 
MEAN a boolean is a tell-tale sign that something is wrong with the 
current bool implementation.

Not that it hasn't been mentioned before ;).

Hauke
May 03 2004
parent "Walter" <newshound digitalmars.com> writes:
"Hauke Duden" <H.NS.Duden gmx.net> wrote in message
news:c752e6$1e7a$1 digitaldaemon.com...

 Walter wrote:

 Generally, a computation of 0 or !0 involves one or two less







 than converting it to 0 or 1.



 type where true simply means !=0.



I'm just one of those people, probably very few in number, who think that C
got it right by using 'int' for it and testing for 0 or !0. It's very
efficient, and I am loathe to give that up for anything less than a
thoroughly compelling reason. It's served me well for 20+ years of C coding.

There are 3 scenarios for a boolean:

1) need it to be fast
2) need a single value to be small
3) need a packed array of boolean values

'int' serves (1) well. D's 'bit[]' serves (3), and 'bit' does double duty by
also being a byte wide value when used outside of an array, serving (2).


 IMHO, your using int instead of bool for a situation where you really
 MEAN a boolean is a tell-tale sign that something is wrong with the
 current bool implementation.



While I see your point, I don't view it that way. I view it as getting
comfortable using an idiom that maps well onto efficient execution on the
hardware. Perhaps one reason I am so comfortable with it is all the
assembler programming I've done.


 Not that it hasn't been mentioned before ;).



Indeed. I recall the usenet flame wars on this back in the 1980's. The
various camps have all long since dug in and well fortified their positions,
so I don't think anyone is going to change their mind <g>.
May 03 2004