HBOUND returns a FIXED BINARY value that specifies the current upper bound of dimension y of x.
>>-HBOUND(x-+----+-)------------------------------------------->< '-,y-'
y can be omitted only if the array is one-dimensional.
Under the CMPAT(V3) compiler option, HBOUND returns a FIXED BIN(63) value. Under the CMPAT(V2) and CMPAT(LE) compiler options, HBOUND returns a FIXED BIN(31) value.