start = schedule

schedule = element schedule { monday, tuesday, wednesday, thursday, friday }
day = title, slot+
monday =
    element day {
        attribute d { "Monday, June 5" },
        day
    }
tuesday =
    element day {
        attribute d { "Tuesday, June 6" },
        day
    }
wednesday =
    element day {
        attribute d { "Wednesday, June 7" },
        day
    }
thursday =
    element day {
        attribute d { "Thursday, June 8" },
        day
    }
friday =
    element day {
        attribute d { "Friday, June 9" },
        day
    }

title = element title { text }
desc =
    element desc {
        mixed { (code | q)* }
    }
code = element code { url?, text }
url = attribute url { xsd:anyURI }
slot = element slot { clocktime, title, desc?, activity+ }
# @clocktime is starting time in "09:00:00" 24-hour format
clocktime = attribute time { xsd:time }
# @durtime format is "PTxHyM", where "PT" is required, "x" is the 
# number of hours and "y" the number of minutes, expressed as integers 
activity = element act { image?, durtime, desc, details? }
durtime = attribute time { xsd:duration }
details = element details { item+ }
item =
    element item {
        mixed { (link | q | code | emph | image | answer)* },
        examples?
    }
image = element image { alt, size, text }
alt = attribute alt { text }
# describes the image
size = attribute size { "icon" | "larger" }
link =
    element link {
        xsd:string { pattern = "\S+" }
    }
q =
    element q {
        mixed { code* }
    }
examples = element examples { example+ }
example =
    element example {
        mixed { (answer | examples | link | q | code | emph | image)* }
    }
emph = element emph { url?, text }
answer =
    element answer {
        type?,
        mixed { (code | emph | link | q)* }
    }
type = attribute type { "inline" | "block" }