How to convert the string "A^0" into the expression Superscript[A,0]?

Question

I'm looking for a procedural way to define a symbol for a variable, based on a string. For instance, ToExpression["A^B"] gives us Power[A,B] (which, might be enough if we know that B will never get any value throughout the code).

However, as soon as we assign a number to B, we start getting troubles. For example, ToExpression["A^0"] evaluates to 1, ToExpression["A^(-1)"] evaluates to 1/A, and so on, but I would like to get Superscript[A,0] and Superscript[A,-1], and so on instead. How can I achieve that?

Answer 1

Something like this?:

convert[str_] := str // StringReplace["^" :> "~Superscript~"] // ToExpression

convert /@ {"A^B", "A^0", "A^-1", "A^(-1)"}
(* {Superscript[A, B], Superscript[A, 0], Superscript[A, -1], 
   Superscript[A, -1]} *)

Another method:

convert[str_] := Block[{Power = Superscript}, ToExpression@str]