WowAce

What steps will reproduce the problem?
1.login
2.
3.

What is the expected output? What do you see instead?

What version of the product are you using?

Do you have an error log of what happened?
1x TankPoints-r161\AceDebug-3.0\AceDebug-3.0-3.lua:114: attempt to call method "argCheck" (a nil value)
TankPoints-r161\AceDebug-3.0\AceDebug-3.0-3.lua:114: in function "SetDebugLevel"
HealPoints\HealPoints-r95.lua:128: in function <HealPoints\HealPoints.lua:116>
(tail call): ?
<in C code>
<string>:"safecall Dispatcher[1]":9: in function <string>:"safecall Dispatcher[1]":5
(tail call): ?
Ace3-r1045\AceAddon-3.0\AceAddon-3.0-11.lua:514: in function "InitializeAddon"
Ace3-r1045\AceAddon-3.0\AceAddon-3.0-11.lua:629: in function <Ace3\AceAddon-3.0\AceAddon-3.0.lua:621>

Locals:
nil

Please provide any additional information below.

This is because HealPoints depends on a newer version of AceDebug, but your TankPoints has an older version.

The fix was to update the TankPoints version of AceDebug with the missing code.

The fix to prevent problems in the first place would be to version AceDebug to a newer version whenever there's a breaking change; so an outdated version will not break people depending on a newer version.

But either way it's fixed (for now)