2 isblk - whether or not a value is a block
13 isblk(val) returns 1 if val is an unnamed block, 2 if val is a
14 named block, 0 otherwise.
16 Note that a named block B retains its name after its data block is
17 freed by rmblk(B). That a named block B has null data block may be
18 tested using sizeof(B); this returns 0 if and only if the memory
41 isassoc, isatty, isconfig, isdefined, iserror, iseven, isfile,
42 ishash, isident, isint, islist, ismat, ismult, isnull, isnum, isobj,
43 isobjtype, isodd, isprime, isrand, israndom, isreal, isrel,
44 issimple, issq, isstr, istype