+%#!luatex
+\input luatexja.sty
+\catcode`\@=11
+\jfont \testA=\ltj@stdmcfont:jfm=ujis/hoge,piyo at 9.62216pt
+\jfont \testB=\ltj@stdmcfont:jfm=ujis/piyo,hoge;jp90 at 9.62216pt
+\jfont \testC=\ltj@stdgtfont:jfm=ujis/;+jp90 at 9.62216pt
+\jfont \testD=\ltj@stdgtfont:jfm=/abcd;+trad at 9.62216pt % error
+\jfont \testE=\ltj@stdmcfont:jfm=ujis/piyo,hoge=2,=4,hoge=true;jp90 at 9.62216pt
+\jfont \testF=\ltj@stdmcfont:jfm=ujis/hoge=true,piyo at 9.62216pt
+% note that metrics of \testA and \testF are different; in \testF, the value of 'hoge' is a string 'true',
+% while that in \testA is a boolean true.
+
+
+\ltjsetparameter{differentjfm=both}
+{\testA (あ葛鴎)}{\testB (い葛鴎)}{\testC (う葛鴎)}(え葛鴎){\tengt(あ葛鴎)}\par
+
+\ltjsetparameter{differentjfm=paverage}
+{\testA (あ葛鴎)}{\testB (い葛鴎)}{\testC (う葛鴎)}(え葛鴎){\tengt(あ葛鴎)}\par
+
+\bye