On Wednesday, 20 November 2013 at 11:25:24 UTC, Jonathan M Davis
wrote:
On Wednesday, November 20, 2013 12:07:25 seany wrote:
Is there any way to represent mixed data (of various types) as
a
single array?
In scilab, we have list, and you can do list(integer, stringvar
....) etc.
Can you do something similar in D? An idea is to use a struct
wil all possible data types, but think that is inefficient.
Any other ideas?
That sounds more like a tuple rather than a list, as lists
normally are
supposed to contain values which all have the same type. So,
the normal thing
to do would probably be to use std.typecons.Tuple. e.g.
auto t = tuple(1, 3.7, "foo");
But that's definitely a tuple and not a list, so you can't
append to it or
remove anything from it or anything like that. If you want an
actual list, you
need a way to make all of the items in the list be the same
type. And if they
don't all share a base type (which pretty much only happens
with classes),
then you'd probably have to use std.variant.Variant, which is
essentially a
typed union. However, I'd advise against using anything like
that unless you
actually need it. You should favor static typing as much as
possible rather
than trying to hold differing types in the same list, as that's
just begging
for bugs, particularly when you then try and use some of those
items as a type
other than what they are.
- Jonathan M Davis
okey, i was thinking of dynamically generating variables, and
returning their addresses to a int []. Ofcourse i first need to
cast it to int.
I have the following cases :
I have a string, this string may take the form of
a.b.c.d.e ...
The function should return
depending on another parameter,one of the following:
1. an array with [a, b, c, d, e]
2. the original string
the original string may also take the form of
(a.(b.c).(((d.e.f).(g.h) .. etc
and depending on the other parameter, we may have
1. array with [a,b,c,d, .. ]
2. array with [1, [b.c] , [[[d,e,f]],[g,h]]
...
n. the string itself
Now, i was trying the first, i used the std.algorithms.splitter,
and the result is of type *Result* and not string[], nonetheless
I can cast (how does this work? isn't typedef removed, and alias
should preserve underlaying types)
Morover while getting the addresses of the array elements, and
putting them in the integer array, all of them returns the same
address : the address of the array. (obviously). hence, i am also
wondering, is there something in D, which can
1. either return the individual addresses of an element of an
array or any type of objects...
2. generate variable names on the fly in RUNTIME?
