Get “actual” length of string in Unicode characters

Question

given a character like \"✮\" (\\xe2\\x9c\\xae), for example, can be others like \"Σ\", \"д\" or \"Λ\") I want to

Answer 1

My answer to a similar question:

You are looking for the rendering width from the current output context. For graphical UIs, there is usually a method to directly query this information; for text environments, all you can do is guess what a conformant rendering engine would probably do, and hope that the actual engine matches your expectations.