object) is by default pasted together
 with other arguments (...) and with seperator sep="".
 For instance, to throw an exception, write
   throw("Value out of range: ", value, ".").
 which is short for
   throw(Exception("Value out of range: ", value, ".")).
 Note that throw() can be defined for specific classes, which can
 then be caught (or not) using tryCatch().## S3 method for class 'default}(...)':
throwundefined
- ...{One or several strings that are concatenated and collapsed
      into on message string.}
Returns nothing. 
rbern <- function(n=1, prob=1/2) {
    if (prob < 0 || prob > 1)
      throw("Argument 'prob' is out of range: ", prob)
    rbinom(n=n, size=1, prob=prob)
  }
  rbern(10, 0.4)
  # [1] 0 1 0 0 0 1 0 0 1 0
  tryCatch(rbern(10, 10*0.4),
    error=function(ex) {}
  ) 
[object Object]
See the Exception class for more detailed information. 
error