Raise r←[x]↗y

x must be a scalar natural. y must be a character vector. If x is not provided, it defaults to 1.

If x is 0, nothing happens and r is the empty vector.

If x is not 0, fails with an error type indexed by x and message y:

xError type
1User error
2Domain error
3Length error
4Rank error
5Not yet implemented!
6Syntax error
7Assertion failed
8Index error
9IO error