Chained calls might result in leaks

[wgebczyk]

When using chained calls arr.filter(...).map(...) and disposing only last chain object it might leak memory. Solution is to intercept each call in chain and "dispose" them.

[ghost]

Can you elaborate on this solution? Do you mean it as a workaround or something that could become a pull request?

[ghost]

bump

[cryo-warden]

Leaks are a common problem with computed observables whose computation-functions read longer-lived observables. I'm not surprised this is also an issue with what are essentially computed arrays.

To eliminate leaks:

• create pure-computed arrays whenever possible (they don't cache their value when unwatched however, so beware inefficient re-computations), and
• dispose non-pure computed arrays when you're done with them.

These steps are needed only because JavaScript lacks weak references. (JavaScript is getting WeakMap, but that's different from a weak reference. WeakMap cannot fix this kind of problem.)

[cryo-warden]

@wgebczyk Noting what I said above about the two ways to avoid leaking memory with computed observables, your only option to prevent leaks with chained calls is to create these chained arrays as pure-computed (since you cannot call their dispose methods). I do not know if this is already a feature of this plugin. If not, then "pure-computed array projection" is the feature you should request.

[JasonKleban]

Thanks! (from MrAndMrsK)