+\DeclareDocumentCommand \renewjfontfamily { m O{} m O{} } {
+ \cs_set_eq:NN \fontspec_set_family:Nnn \ltj_fontspec_set_family:Nnn
+ \renewfontfamily #1 [#2,#4] {#3}
+ \cs_set_eq:NN \fontspec_set_family:Nnn \__ltj_orig_fontspec_set_family:Nnn
+}
+\DeclareDocumentCommand \setjfontfamily { m O{} m O{} } {
+ \cs_set_eq:NN \fontspec_set_family:Nnn \ltj_fontspec_set_family:Nnn
+ \setfontfamily #1 [#2,#4] {#3}
+ \cs_set_eq:NN \fontspec_set_family:Nnn \__ltj_orig_fontspec_set_family:Nnn
+}