isdefined(myobject, :myfield)
On Tuesday, July 22, 2014 6:54:00 PM UTC-4, Ben Ward wrote: > > I have a type that contains references to other instances of the same type > - like a doubly linked list or - as it's intended use, like a tree like > structure. They contain references to a parent of the same types and an > array of references to children of the same type. However a root or singly > constructed instance of the type will not start out with a parent or > children and so these fields will be #undef, how can I check for #undef > fields? It didn't say in the types section in the manual, although it did > say accessing it is an automatic error so I guess a try block might work - > but I don't know if try blocks are preferable in Julia to simply > anticipating the #undef. I've normally heard the mantra of anticipating an > expected exception rather than make excessive try catches. > > Thanks. >
