On Tue, Apr 28, 2009 at 4:05 PM, Don Watson <[email protected]> wrote: > You say: > > "So if [ and ] were exact replacements for x and y, > Skip's example would be syntactically invalid. > > But y is a noun -- it is not a verb." > > Do you see the contradiction here? > > I am not saying that y as a noun is replaced by another noun. I am > saying that it is replaced by the noun phrase "]y" which produces the same > result in this situation.
But not in all situations. Unfortunately, we would probably need to have half a dozen different situations to illustrate this point. If we just have one situation, it's probably possible to pick an interpretation which works in that situation but not in others. > To make the inclusion of y implicit, the y is > removed, Thus the symbol "y" is replaced by the symbol "]" - but this > doesn't mean that the noun y is replaced by a noun "]". This is identical to > the way Skip is doing it in tacit J. He too is replacing a symbol "y" with a > verb "]", but he can do that because a noun implicitly follows the verb "]". Your description of what Skip did is an oversimplification -- it describes the instance but does not describe the general case. Here's a hasty example of a case where you can not replace y with ] '1 2 3/4 5/' 4 :'(y + ".);._2 x' 7 8 9 10 11 12 0 Do you understand why you can not replace y with ] in this example? -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
