Nothing to see here :) Exponential time is sometimes confused with [quadratic time], however. Perhaps we need a page somewhere that discusses performance in a more abstract way. For example, there is a hierarchy of performance metrics: * Constant time - O(1) * Linear time - O(n) * [Quadratic time] - O(n**2) * Polynomial time * Exponential time * ? Some [Tcl] operations are likely to fall into these categories in a predictable way, and some not. It might be interesting to categorize some of the [dict], [list], and [array] operations to see how they behave. ---- [Category Performance]