Basic Examples 
(2)
 

Flatten out keys in an
Association
:
In[60]:=
assoc=<|
k
1
<|
k
11
a,
k
12
b|>,
k
2
<|
k
21
<|
k
211
c,
k
212
d|>|>,
k
3
<||>,
k
4
e|>
Out[60]=

k
1

k
11
a,
k
12
b,
k
2

k
21

k
211
c,
k
212
d,
k
3
,
k
4
e
In[61]:=
[◼]
AssociationKeyFlatten
[assoc]
Out[61]=
{
k
1
,
k
11
}a,{
k
1
,
k
12
}b,{
k
2
,
k
21
,
k
211
}c,{
k
2
,
k
21
,
k
212
}d,{
k
4
}e
Apply a function to flattened lists of keys:
In[62]:=
[◼]
AssociationKeyFlatten
[assoc,f]
Out[62]=
f[{
k
1
,
k
11
}]a,f[{
k
1
,
k
12
}]b,f[{
k
2
,
k
21
,
k
211
}]c,f[{
k
2
,
k
21
,
k
212
}]d,f[{
k
4
}]e