Copy a TYPE (object)

[Munair]

I did a search here in the forum but could not find an explicit answer.

If I want to fully copy a TYPE rather than creating a second reference to the same TYPE, does the compiler do that for me with:

Code: Select all

bTypeCopy = aType

or would it require a Cast construction?

[D.J.Peters]

asignment = : https://www.freebasic.net/wiki/wikka.ph ... Assignment
overloading asignment LET: https://www.freebasic.net/wiki/wikka.ph ... KeyPgOpLet

[Munair]

Thanks that's a great thing. So if I understand correctly assigning one type (object) instance to another actually creates a new copy, rather than a copy of the same reference. This example seems to indicate that this is indeed the case:

Code: Select all

type aType
	x as integer
end type

dim as aType a, b

a.x = 5

b = a
print b.x

a.x = 2
print b.x 'still 5
end

So in order to create a new reference (for whatever purpose) one needs to explicitely copy the pointer. In RealBasic it was the opposite forcing one to manually copy each member. PureBasic has CopyStructure() to achieve the same thing.

[D.J.Peters]

if you need a "deep" copy you can overload "=" with let.

by the way you can view the translated FreeBASIC program as C-code or as assembler listing

asignment of a struct is a memcpy(target,source,sizeof(user_type))

Joshy

[Munair]

OK, thanks

[fxm]

Another variant is to make a copy-construction ('b') from the first instance ('a') after its initialization:

Code: Select all

type aType
   x as integer
end type

dim as aType a

a.x = 5

dim as aType b = a
print b.x

a.x = 2
print b.x 'still 5

sleep