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.