/* Title: Pure/Thy/thy_info.scala
Author: Makarius
Theory and file dependencies.
*/
package isabelle
class Thy_Info(thy_load: Thy_Load)
{
/* messages */
private def show_path(names: List[Document.Node.Name]): String =
names.map(name => quote(name.theory)).mkString(" via ")
private def cycle_msg(names: List[Document.Node.Name]): String =
"Cyclic dependency of " + show_path(names)
private def required_by(initiators: List[Document.Node.Name]): String =
if (initiators.isEmpty) ""
else "\n(required by " + show_path(initiators.reverse) + ")"
/* dependencies */
type Dep = (Document.Node.Name, Document.Node.Header)
private type Required = (List[Dep], Set[Document.Node.Name])
private def require_thys(initiators: List[Document.Node.Name],
required: Required, names: List[Document.Node.Name]): Required =
(required /: names)(require_thy(initiators, _, _))
private def require_thy(initiators: List[Document.Node.Name],
required: Required, name: Document.Node.Name): Required =
{
val (deps, seen) = required
if (seen(name)) required
else if (thy_load.loaded_theories(name.theory)) (deps, seen + name)
else {
try {
if (initiators.contains(name)) error(cycle_msg(initiators))
val header =
try { thy_load.check_thy(name) }
catch {
case ERROR(msg) =>
cat_error(msg, "The error(s) above occurred while examining theory " +
quote(name.theory) + required_by(initiators))
}
val (deps1, seen1) =
require_thys(name :: initiators, (deps, seen + name), header.imports)
((name, header) :: deps1, seen1)
}
catch {
case e: Throwable =>
((name, Document.Node.bad_header(Exn.message(e))) :: deps, seen + name)
}
}
}
def dependencies(names: List[Document.Node.Name]): List[Dep] =
require_thys(Nil, (Nil, Set.empty), names)._1.reverse
}