better makefile

diff --git a/helm/software/matita/contribs/didactic/Makefile b/helm/software/matita/contribs/didactic/Makefile
index bc35339e7865db2aa2ac167969e9642c725a5aff..68f956a2409243d025d36a4aa4b12b771d8d4499 100644 (file)
--- a/helm/software/matita/contribs/didactic/Makefile
+++ b/helm/software/matita/contribs/didactic/Makefile
@@ -14,9 +14,6 @@ depend:
        $(BIN)matitadep -dot && rm depends.dot
 depend.opt:
        $(BIN)matitadep.opt -dot && rm depends.dot
-exercise:
-       rm -rf ex/
-       mkdir ex/
-       cp *.ma depends ex/
-       for X in ex/*.ma; do perl -ne 'undef $$/;s/\(\*BEGIN.*?END\*\)/.../msg;print' -i $$X; done
-       echo 'baseuri=cic:/matita/didactic/student' > ex/root
+exercise-%: %
+       cp $< $@
+       perl -ne 'undef $$/;s/\(\*BEGIN.*?END\*\)/.../msg;print' -i $@