/db/apps/SQLTutor/main.xqexerr:ERROR XPTY0004: The actual cardinality for parameter 1 does not match the cardinality declared in the function's signature: local:step-type($step as element()) xs:string. Expected cardinality: exactly one, got 0. [at line 247, column 55, source: /db/apps/SQLTutor/main.xq]
In function:
local:step-type(element()) [247:38:/db/apps/SQLTutor/main.xq]
local:show-intro(item()*, item()*) [247:15:/db/apps/SQLTutor/main.xq]
local:show-step() [458:1:/db/apps/SQLTutor/main.xq]