# meaning of variable equal dot [closed]

I came across a program which I have written in a simplified form.

For[i=1,i<100, i=i+1;
func = a x^i;
func=.
];


What is purpose of "func=."?

• A tip: whenever you encounter an unfamiliar symbol like =. in Mathematica, highlight it and press F1. – J. M.'s technical difficulties Mar 28 '18 at 17:29
• =. removes any rules defined for the left-hand-side. – David G. Stork Mar 28 '18 at 17:54
• – AccidentalFourierTransform Mar 28 '18 at 23:33

=. removes any rules defined for the left-hand side.