Would you be willing to provide an example of the "multiple incompatible implementations of the same macro" situation happening in the real world? I've been wri

Would you be willing to provide an example of the "multiple incompatible implementations of the same macro" situation happening in the real world? I've been writing (modest) macros in CL for several years now, and never seen this occur - I've only seen "upgrading" where macro authors layer functionality onto existing macros in such a way that is mostly compatible with the original (such as sjl's extension of WHEN-LET/IF-LET to WHEN-LET* / IF-LET* [1], which I believe are compatible with the Alexandria implementations of the former), although it's quite likely that I simply don't have the experience to have encountered this situation. [1] http://stevelosh.com/blog/2018/07/fun-with-macros-if-let/ http://stevelosh.com/blog/2018/07/fun-with-macros-if-let/