xcoffins.pdf. - CTAN

\JoinCoffins The \JoinCoffins function needs to do a bit of work on the input syntax, as there are
a number of optional arguments to worry about. The idea here is that \JoinCoffins
can be used to either expand the bounding box of 〈coffin1 〉 or add 〈coffin2 〉 without any
expansion of the bounding box. There are also the two handle positions and the offset
to sort out.
76 \NewDocumentCommand \JoinCoffins
77 {
78 o
79 s
80 m
81 > { \SplitArgument { 1 } { , } } O { H , l }
82 m
83 > { \SplitArgument { 1 } { , } } O { H , l }
84 > { \SplitArgument { 1 } { , } } D ( ) { 0 pt , 0 pt }
85 }
86 {
87 \IfNoValueTF {#1}
88 {
89 \IfBooleanTF #2
90 { \coffin_attach:NnnNnnnn #3 #4 #5 #6 #7 }
91 { \coffin_join:NnnNnnnn #3 #4 #5 #6 #7 }
92 }
93 {
94 \group_begin:
95 \keys_set:nn { coffin } {#1}
96 \tl_set:Nx \l__coffin_tmp_tl
97 {
98 \group_end:
99 \bool_if:NTF \l__coffin_bound_box_grow_bool
100 { \coffin_join:NnnNnnnn }
101 { \coffin_attach:NnnNnnnn }
102 \exp_not:N #3
103 { \exp_not:o { \l__coffin_A_hpole_tl } }
104 { \exp_not:o { \l__coffin_A_vpole_tl } }
105 \exp_not:N #5
106 { \exp_not:o { \l__coffin_B_hpole_tl } }
107 { \exp_not:o { \l__coffin_B_vpole_tl } }
108 { \dim_use:N \l__coffin_hoffset_dim }
109 { \dim_use:N \l__coffin_voffset_dim }
110 }
111 \l__coffin_tmp_tl
112 }
113 }
(End definition for \JoinCoffins. This function is documented on page 5.)
\TypesetCoffin For typesetting coffins there are two optional arguments, both of which need to be split.
This is a simpler case of the code needed for \JoinCoffins.
114 \NewDocumentCommand \TypesetCoffin
115 {
12