[6330] in s-news-athena
Zero-argument functions
daemon@ATHENA.MIT.EDU (Russ Lenth)
Tue Jan 31 14:16:06 1995
Date: Tue, 31 Jan 95 12:46:30 CST
From: rlenth@stat.uiowa.edu (Russ Lenth)
To: s-news@utstat.toronto.edu
Paul Tukey responded to my earlier posting on quitting S as follows...
> Why not go one step further and add:
>
> class(q) <- "QUIT"
>
> Then even "q" would have the desired effect!
That got me to thinking... Define a print method like this:
print.CHEAT <- function(fcn)
get(as.character(substitute(fcn)))()
Now, you can make any zero-argument function execute
without parentheses. For example,
class(q) <- "CHEAT"
class(help) <- "CHEAT"
class(X11) <- "CHEAT"
creates parenthesis-free commands "q", "help", and "X11".
There's undoubtedly a more refined method that does not require
one to make a private copy of a whole function.
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