Paren
Parentheses and Braces
Open parenthesis, (
, and open brace, {
, are
.Primitive
functions in R.
Effectively, (
is semantically equivalent to the identity
function(x) x
, whereas {
is slightly more interesting,
see examples.
- Keywords
- programming
Usage
( ... )
{ ... }
Value
-
For
(
, the result of evaluating the argument. This has
visibility set, so will auto-print if used at top-level.For {
, the result of the last expression evaluated. This has
the visibility of the last evaluation.
References
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
See Also
if
, return
, etc for other objects used in
the R language itself.
Syntax
for operator precedence.
Examples
library(base)
f <- get("(")
e <- expression(3 + 2 * 4)
identical(f(e), e)
do <- get("\{")
do(x <- 3, y <- 2*x-3, 6-x-y); x; y
## note the differences
(2+3)
{2+3; 4+5}
(invisible(2+3))
{invisible(2+3)}