As documented, a new command \⟨name⟩ defined by \newtcbox[⟨init options⟩]{\⟨name⟩}[⟨number⟩][⟨default⟩]{⟨options⟩} or \newtcboxfit takes ⟨number⟩+1 arguments. With current implementation, the last mandatory argument is curried thus \⟨name⟩ can take at most 10 arguments.
Will the behavior of "at most 10 arguments" be kept in future releases? If so maybe it's worth being documented, because when reading the docs I got the question, can ⟨number⟩ still be up to 9?`
Similarly, a new command \⟨name⟩ defined by \NewTCBox[⟨init options⟩]{\⟨name⟩}{⟨specification⟩}{⟨options⟩} and \NewTCBoxFit now can take at most 10 arguments, as if it was defined with arg-spec ⟨specification⟩ m. (The behavior of taking an extra mandatory argument beyond ⟨specification⟩, is not documented!)
Also note a subtle difference: the trailing optional arguments in ⟨specification⟩, if exist, can still be modified by !. That is, \NewTCBox\mybox{!o}{} works while \NewDocumentCommand\mycmd{!o m}{} errors, because no mandatory arguments can appear after !-modified opt-arg. See texdoc usrguide, sec. 2.6 "Spacing and optional arguments" for more info.
As documented, a new command
\⟨name⟩defined by\newtcbox[⟨init options⟩]{\⟨name⟩}[⟨number⟩][⟨default⟩]{⟨options⟩}or\newtcboxfittakes⟨number⟩+1arguments. With current implementation, the last mandatory argument is curried thus\⟨name⟩can take at most 10 arguments.Will the behavior of "at most 10 arguments" be kept in future releases? If so maybe it's worth being documented, because when reading the docs I got the question, can
⟨number⟩still be up to 9?`Similarly, a new command
\⟨name⟩defined by\NewTCBox[⟨init options⟩]{\⟨name⟩}{⟨specification⟩}{⟨options⟩}and\NewTCBoxFitnow can take at most 10 arguments, as if it was defined with arg-spec⟨specification⟩ m. (The behavior of taking an extra mandatory argument beyond⟨specification⟩, is not documented!)Also note a subtle difference: the trailing optional arguments in
⟨specification⟩, if exist, can still be modified by!. That is,\NewTCBox\mybox{!o}{}works while\NewDocumentCommand\mycmd{!o m}{}errors, because no mandatory arguments can appear after!-modified opt-arg. Seetexdoc usrguide, sec. 2.6 "Spacing and optional arguments" for more info.