The type for log sources.

create ?doc name is a new log source. name is the name of the source; it doesn't need to be unique but it is good practice to prefix the name with the name of your package or library (e.g. "mypkg.network"). doc is a documentation string describing the source, defaults to "undocumented". The initial reporting level of the source is defined by Logs.level.

name is src's name.

doc src is src's documentation string.

level src is the report level of src (if any).

set_level src l sets the report level of src to l. Only applications should use this function directly, see usage conventions.

equal src src' is true iff src and src' are the same source.

compare src src' is a total order on sources.

pp ppf src prints an unspecified representation of src on ppf.

list () is the current exisiting source list.