Check
Check[expr,failexpr]
evaluates expr, and returns the result, unless messages were generated, in which case it evaluates and returns failexpr.
Check[expr,failexpr,{s1::t1,s2::t2,…}]
checks only for the specified messages.
Check[expr,failexpr,"name"]
checks only for messages in the named message group.
Details

- Check has attribute HoldAll.
- Check does not test for messages that have been switched off using Off, or by uses of Quiet that occur inside it.
- The operation of Check is not affected by being enclosed inside Quiet.
- In Check[expr,failexpr,"name"], possible named message groups are given by $MessageGroups.
- Explicit message names of the form s::t can be mixed with named message groups.
Introduced in 1988
Updated in 2008
(1.0)
|
(7.0)