# Stretchable delimiters ignoring overline

I would like adjustable delimiters to ignore overlines. For example:

\documentclass{article}
\begin{document}
$\left\{ f \right\} \; \left\{ \overline{f} \right\}$
\end{document}


The braces in the right case are noticeably larger than in the left case. I would like adjustable delimiters to produce the same output in both cases.

Any idea how could I do this?

• \vphantom{f}\smash{\overline{f}} – Steven B. Segletes Jun 9 '16 at 12:38
• Just omit \left and \right. – egreg Jun 9 '16 at 13:05
• @egreg, while your suggestion addresses the use-case of the OP's MWE, there are many other use cases (fractions, square roots, exponents, etc) where the issue still comes into play. I mention that for other readers, since I know that you know that already. – Steven B. Segletes Jun 9 '16 at 13:18
• @StevenB.Segletes -- but implicit in egreg's comment is that it's more often than not a bad idea to use \left and \right, but to select the appropriate size intentionally. granted, doing this well comes only with experience, but too many authors always use \left and \right (and so do some "helpful" input software aids), and the resulting mess causes real problems in a publishing production environment. this is a "best practices" situation. – barbara beeton Jun 9 '16 at 13:35
• @barbarabeeton No argument from me on that one. And you are right that it is a trap that is fallen into easily by novice users. – Steven B. Segletes Jun 9 '16 at 13:37

Here, I introduce \noverline{}. You probably want to use it only when needed.
\documentclass{article}
$\left\{ f \right\} \; \left\{ \noverline{f} \right\}$