«

What I mean is, if I repeatedly call a String's hash method (i.e. like
using it regularly to access a Hash) will the hash value get
recalculated every time?






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http://www.it-is-truth.org/

On Tue, 2003-12-23 at 01:56, Asfand Yar Qazi wrote:
> What I mean is, if I repeatedly call a String's hash method (i.e. like
> using it regularly to access a Hash) will the hash value get
> recalculated every time?

Yes, it will. Have you considered unsing Symbols instead of Strings?
The hash value "calculation" of a Symbol is O(1).

--
o=lambda{|o|p o};O=Struct.new(:a,:b,:c);e=%q(_(?h,_(?h,_(?\ ,_(?s,_(?u,_(74)),
_(?t)),_(?t,_(?o,_(?n,_(?a))))),_(82,_(?r,_(?e),_( 32)),_(32,_(98,_(?u),_(?y)))
)),_(?r,_(99,_(97),_(?k,nil,_(?e))),_(10))));def _(*a)O.new(*a)end;class O;def
e(&o)b&&b.e(&o);o[a];c&&c.e(&o)end;end;def p(o)print(''<<o)end;eval(e).e(&o)

Florian Frank wrote:
> On Tue, 2003-12-23 at 01:56, Asfand Yar Qazi wrote:
>
>>What I mean is, if I repeatedly call a String's hash method (i.e. like
>>using it regularly to access a Hash) will the hash value get
>>recalculated every time?
>
>
> Yes, it will. Have you considered unsing Symbols instead of Strings?
> The hash value "calculation" of a Symbol is O(1).
>

Depends... if Symbols are used as the keys for a hash table, can they be
as easily accessed from extension modules as if Strings were used?







--
http://www.it-is-truth.org/

il Wed, 24 Dec 2003 00:11:27 +0000, Asfand Yar Qazi
<im_not_giving_it_here@i_hate_spam.com> ha scritto::


>>
>> Yes, it will. Have you considered unsing Symbols instead of Strings?
>> The hash value "calculation" of a Symbol is O(1).
>>
>
>Depends... if Symbols are used as the keys for a hash table, can they be
>as easily accessed from extension modules as if Strings were used?

why the should'nt ? Many lybraries make use of symbols as constants,
ruby-gtk or Pdf::Writer are examples.. and, btw "everything is an
object" make everything work as everything else

On Wed, 2003-12-24 at 01:06, Asfand Yar Qazi wrote:
> Depends... if Symbols are used as the keys for a hash table, can they be
> as easily accessed from extension modules as if Strings were used?

You can use ID2SYM(rb_intern("foo")) to get the VALUE of symbol :foo. I
don't think it's too complicated.

--
o=lambda{|o|p o};O=Struct.new(:a,:b,:c);e=%q(_(?h,_(?h,_(?\ ,_(?s,_(?u,_(74)),
_(?t)),_(?t,_(?o,_(?n,_(?a))))),_(82,_(?r,_(?e),_( 32)),_(32,_(98,_(?u),_(?y)))
)),_(?r,_(99,_(97),_(?k,nil,_(?e))),_(10))));def _(*a)O.new(*a)end;class O;def
e(&o)b&&b.e(&o);o[a];c&&c.e(&o)end;end;def p(o)print(''<<o)end;eval(e).e(&o)

Hi,

At Tue, 23 Dec 2003 09:56:53 +0900,
Asfand Yar Qazi wrote:
> What I mean is, if I repeatedly call a String's hash method (i.e. like
> using it regularly to access a Hash) will the hash value get
> recalculated every time?

Hash (accurately, st library) has cache, but String doesn't.

--
Nobu Nakada

Florian Frank wrote:
> On Wed, 2003-12-24 at 01:06, Asfand Yar Qazi wrote:
>
>>Depends... if Symbols are used as the keys for a hash table, can they be
>>as easily accessed from extension modules as if Strings were used?
>
>
> You can use ID2SYM(rb_intern("foo")) to get the VALUE of symbol :foo. I
> don't think it's too complicated.
>

WOW DAT WAS KWICK U R LEE7!!!11111





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http://www.it-is-truth.org/