OpenEuphoria

Re: sequence question

• Posted by CoJaBo <cojabo at suscom.net> Sep 04, 2004
• 482 views

Tone Škoda wrote:
> 
> sequence s1, s2
> s1 = repeat (0, 1000000) -- s1 is 3.8MB big
> s2 = {{}}
> s2 [1] = s1
> 
> will this last line of code:
> 1. make copy of s1 into s2 [1]
> 2. or will it only make pointer to s1?
2

> 
> similar is this:
> s2 = {repeat (0, 1000000)}
> s1 = s2 [1] -- what happens here?
2 again

> 
> if it is number 1 then it is waste of memory.
> in cases like this i like C more because it is more clear what happens.
> 
> i'm asking this because i want to create a library which is not specific for
> program.
> and in this library one sequence1 appears in many different sequences. i could
> only
> have one copy of this sequence1, not many same copies which would exist in
> these different
> sequences. here pointers would be nice.
> 
> i would like pointers and structures added to euphoria.
> pointers are good because you can identify a variable without having to copy
> it in
This happens automattically, but pointers could be useful is some cases
(there are better uses than this):

integer a,b
atom c

a=~b--a is (internally) a pointer to b(~ here specifies a pointer)
--a and b are still undefined

a=1
?b--displays 1

b=2
?a--displays 2

a=~c--Should cause an error; types must be the same

Unfortunatly, this will probably never be implemented.

> memory. you can do that in euphoria but it's much more complicated. structures
> are
> also possible in euphoria but again not on simple easy way. and structures are
> needed
> in every program.
There are librarys that can do ths easily, there isn't really much to improve.

>