Elegance arises from the concise use of existing and suitable features to achieve the desired effect. Ideally, at least in my view, the solution to the problem can be stated in a declarative rather than a procedural fashion.
While I would concede that the former is not necessarily more concise, its implicit usage of features required to solve the problem will contribute to the elegance of the solution put forward. Solutions involving an explicit loop stepping through a string character-by-character hence certainly are transparent to inspection ... but way too procedural to be surprising or elegant.