I understand that if I have the field operators $\psi(r)$ and $\psi^\dagger(r)$, then I have the canonical commutation relation (in the boson case) $$[ \psi(r) , \psi^\dagger(r')]=\delta(r-r').$$ My question is that if during manipulation of an equation I want to use the commutator, but both field operators are evaluated at zero, then I have $$[ \psi(0) , \psi^\dagger(0)]=\delta(0).$$ But $\delta(0)$ does not seem to be well defined even under the integral. I know I'm missing something really simple here.
I suppose my question then is what explicitly is the value of the commutator $[ \psi(0),\psi^\dagger(0)]$?