All-- Each non-assigment step in a computation produces copies(!) of its inputs, selected and arranged in various specified ways, awaiting disposition--in another step, in assignment to storage, in output, or in discard.
At the very least, any recipe for processing an array should begin with some version of "Take a copy of y, then...", and consistently refer to that copy, rather than to y. As an example, the page for Nub currently contains the following statements: Removes duplicates from a list <https://code.jsoftware.com/wiki/Vocabulary/AET#List>. More generally, removes any item <https://code.jsoftware.com/wiki/Vocabulary/AET#Item> of an array <https://code.jsoftware.com/wiki/Vocabulary/AET#Array> that matches a preceding item. 1. Remove duplicate values <https://code.jsoftware.com/wiki/Vocabulary/Glossary#Value> from a lis <https://code.jsoftware.com/wiki/Vocabulary/AET#List>t 2. Remove duplicate rows from a table <https://code.jsoftware.com/wiki/Vocabulary/AET#Table> I recommend replacing them with: Copies items from a list, omitting duplicates. More generally, omits any item <https://code.jsoftware.com/wiki/Vocabulary/AET#Item> of an array <https://code.jsoftware.com/wiki/Vocabulary/AET#Array> that matches a preceding item. 1. Omit duplicate values <https://code.jsoftware.com/wiki/Vocabulary/Glossary#Value> from a lis <https://code.jsoftware.com/wiki/Vocabulary/AET#List>t 2. Omit duplicate rows from a table <https://code.jsoftware.com/wiki/Vocabulary/AET#Table> The language used to describe a verb often suggests that its result will somehow replace the values being operated on, which will be (nearly) accurate only if followed immediately by re-assignment to the same, named, argument. I urge that any new documentation observe this distinction, and that any definition being updated follow this pattern. If there is a consensus that this is a worthy cause, I shall be willing to propose such changes where I may encounter them in coming months. --Art ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
