TL;DR
inserters can get stuck holding an item. if they could put items into locked slots, they wouldn't (usually)What ? (option 1)
add a boolean to allow inserters to place items into locked slotsbut don't count locked slots when inserters pick up items. keep that the same as it is now
this boolean could be:
- in the UI for the container
- in the scripting API for the container
- in the prototype for the container
- in the UI for the inserter
- in the scripting API for the inserter
- in the prototype for the inserter
if i had to pick one, it'd be the scripting API for the container. it's the most flexible, without changing vanilla
Alternative
Allow a dedicated "overflow" filter for inventory slots (maybe use the "everything" virtual signal icon?), that is prioritized after other slots, and counts as locked when inserters are picking up items.Why ?
in vanilla (or in a standalone mod that added it to the UI) it would make multi-item train stops much less of a hassleit would also simplify how multi-item train stops are handled in mods like LTN and Project Cybersyn. those mods currently set the cargo wagon to have filtered slots, plus a few empty ones, and expect the player to use circuits to avoid overfilling. with this change, they could leave a few locked slots instead, and regular inserters would do the right thing with only a circuit to make sure a train is stopped
it would also make mods that add filterable inventories nicer (i have one called "hub ship", which makes the crashed ship's inventory filterable). you could chain filterable chests together with inserters, and have them mostly behave nicely without a mess of circuits