col­lect­box – Col­lect and pro­cess macro ar­gu­ments as boxes

The pack­age pro­vides macros to col­lect and pro­cess a macro ar­gu­ment (i.e., some­thing which looks like a macro ar­gu­ment) as a hor­i­zon­tal box rather than as a real macro ar­gu­ment.
The “ar­gu­ments” are stored as if they had been saved by \save­box or by the lr­box en­vi­ron­ment. Group­ing to­kens \bgroup and \egroup may be used, which al­lows the user to have the be­gin­ning and end of a group in dif­fer­ent macro in­vo­ca­tions, or to place them in the be­gin and end code of an en­vi­ron­ment. Ar­gu­ments may con­tain ver­ba­tim ma­te­rial or other spe­cial use of char­ac­ters.
The macros were de­signed for use within other macros.