[fpc-pascal] Re: Why this evaluates on "if" wrong ?

Daniël Mantione daniel.mantione at freepascal.org
Mon Oct 29 22:23:09 CET 2007



Op Mon, 29 Oct 2007, schreef L:

> > Same as ansistring.. it can be dangerous to hide all the intricate details of
> a
> > pchar/bytearray, which is what ansistring does. But ansistrings are really
> > useful for 'every day' use.
> 
> > > Wrong. A string can be represented "alphadequate", as it is called; an
> > > ansistring can handle any string you can imagine supposed there is enough
> > > memory available.
> 
> http://www.google.ca/search?q=alphadequate

Noted. Perhaps the reason is it is written with an alpha sign in my books.

> > An adequate or alphadequate representation of a real number cannot exists.
> > Regardless what datastructure you use, there always exists a real number
> > that cannot be represented by it.
> 
> A string with infinite characters cannot be represented.
> Therefore, there is always a string that cannot be represented.

This is the difference between adequate and alphadequate. 
Alphadequate="supposed there is enough memory available". Supposed you 
have enough memory, you can store any string.

On the other hand a Pascal boolean is adequate for storing a 
mathematical boolean, regardless how much memory you have.

And, as said before, no datastructure is adequate for storing a 
mathematical real number. Not even if you have infinite memory.

Daniël


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