# Clearing ::usage message

After having assigned the usage message to f using

ClearAll@f;
f::usage=ToString@RandomInteger@{10^10,10^11};


the mouseover message is stuck at the first assignment while ?f shows the freshest usage message.

How to clear and reassign the usage message so even mouseover is updated?

Env:
Mathematica 12.0 on Win10

• You have use Remove to get rid of usage messages. – m_goldberg Jan 24 '20 at 23:43
• @m_goldberg works! I'll accept if you answer... why doesn't ClearAll work though? – lineage Jan 25 '20 at 3:17

## 1 Answer

It seems one can use the following to force the front-end to update the usage templates (starting in version 12.0):

FECacheTemplateAndUsage["f"]
`

Please note that the front-end will not update the templates even if you set a new usage message. Simply call the above again to force the update once again.

• I think the packet this calls has existed since 11 – b3m2a1 Jan 29 '20 at 23:16
• @b3m2a1 For me, it doesn't seem to work: I get "Could not process unknown packet "CacheTemplateAndUsagePacket"" if I try it in 11.3. Am I missing something? – Lukas Lang Jan 30 '20 at 8:40
• not really sure but I think it it did work – b3m2a1 Jan 30 '20 at 8:42