is mentioned by

Thm* the_w:World, i:Id, t:. Thm* m(i;t)  {m:Msg(the_w.M)| source(mlnk(m)) = i } List	[w-m_wf]
Def withlnk(l;mss) == mapfilter(ms.2of(ms);ms.mlnk(ms) = l;mss)	[w-withlnk]
Def onlnk(l;mss) == filter(ms.mlnk(ms) = l;mss)	[w-onlnk]
Def World Def == T:IdIdType Def == TA:IdIdType Def == M:IdLnkIdType Def == (i:Id(x:IdT(i,x)))(i:Idaction(w-action-dec(TA;M;i))) Def == (i:Id({m:Msg(M)| source(mlnk(m)) = i } List))Top	[world]

In prior sections: mb event system 1

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