User blog comment:Testitemqlstudop/FPT 2/@comment-44130370-20191112022731/@comment-35470197-20191112032620

It is ill-defined because:
 * 1) You have not specified the meaning of the unusual use of \(\mapsto\).
 * 2) You have not specified the meaning of \(@\).
 * 3) You have not specified the domain of \(f\).
 * 4) You have not specified the rule for the confliction of two definitions. (Line 2 and 4, for example.)
 * 5) You have not specified the meaning of \(\vdots\).
 * 6) You have not specified the domain of \(r\).