Handling of braces inside “proxy keys” (e.g. minimum size)

[pgf-tikz-bot]

Migrated from SourceForge
Author: wrtlprnft
Timestamp: 2016-05-09 10:26:15.740000

https://sourceforge.net/p/pgf/bugs/_discuss/thread/8cb5876b/990a/attachment/pgfuseplotmark.png
(This bug report is the result of a discussion on TeX.sx)

TikZ has several shorthand keys for setting two other keys to the same value. For example, there is the triplet (minimum width, minimum height, minimum size) in the shapes module, where the latter key is defined as follows:

\pgfset{minimum size/.style={/pgf/minimum width=#1,/pgf/minimum height=#1}}

This causes problems when trying to include math expressions in such settings. For example, \tikzset{minimum size={max(1,2)}} does not work. The comments in the linked post contain various workarounds, but is there a reason why the definition does not include extra braces like in the following example?

\pgfset{minimum size/.style={/pgf/minimum width={#1},/pgf/minimum height={#1}}}

A command such as

grep -R '\.style=.*=#1' texmf-dist/tex/generic/pgf

finds 25 similar cases.