Regarding the possible response patterns for the numeric interaction type, my understanding is that there are four possible combinations:
'2[:]4' // would mean a minimum of 2 and a maximum of 4 (response in the range of 2 to 4 would be correct)
'4' // (no delimiter) means there is a single correct answer of 4
'4[:]' // this means a minimum of 4 and no maximum (response in the range of 4 or above would be correct)
'[:]4' // would mean no minimum but a maximum of 4.
My question relates to the last example. Would an answer of 0 (zero), or some negative number, be acceptable? The standard does not seem to make any provision for such situations and I am unclear whether values of zero or less were within the contemplation of the drafters of the specification.
Note that the response pattern '-2[:]4'
works in the SCORM Cloud LRS but I am not sure whether other LRSs would accept negative range values.