[Issue 4179] Deleting items from an associative array iterated over

[d-bugmail at puremagic.com]

http://d.puremagic.com/issues/show_bug.cgi?id=4179



--- Comment #9 from bearophile_hugs at eml.cc 2013-07-20 04:05:58 PDT ---
(In reply to comment #8)
> There are more possible ways to make it safe than this.
> 
> One way is to have a list of current iterations associated with each AA. Any
> time an item is removed, any current iterations are also updated. The nodes of
> the list can be stored on the stack of aaApply or whatever function does the
> "foreach" for AAs. It can be as simple as one pointer in the AA structure, and
> a structure with two fields ("current iteration item" / "next list node") on
> the stack - this should allow everything to "just work" and have a small impact
> on performance.
> 
> Alternatively, when items are removed from an AA they can be left for the GC to
> collect rather than deleted explicitly, and their "next" pointer can be set to
> a magic value indicating that they were deleted (e.g. cast(void*)1).

My suggestion was for the foreach to set a boolean flag inside the associative
array, and reset it when the foreach ends. Then the AA.delete should look for
this flag and throw an exception if it's set.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------