• ← Constant
• → HoldAll

Flat

WMA link

Flat

is an attribute that specifies that nested occurrences of a function should be automatically flattened.

A symbol with the Flat attribute represents an associative mathematical operation:

• • SetAttributes[f, Flat]

• • f[a, f[b, c]]

Flat is taken into account in pattern matching:

• • f[a, b, c] /. f[a, b] -> d