Finsupp.update_eq_single_add_erase

∀ {ι : Type u_1} {M : Type u_3} [inst : AddZeroClass M] (f : ι →₀ M) (a : ι) (b : M),
  f.update a b = (fun₀ | a => b) + Finsupp.erase a f

Defined in: Mathlib.Algebra.Group.Finsupp
Cited by: 2 results in Mathlib
Foundations: Depth 67 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes: AddZeroClass

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