TITLE(expression @@ Unevaluated Expressions)
USAGE(
expression(DOTS)
BLANK
is.expression(expr)
as.expression(expr)
)
ALIAS(expression)
ALIAS(is.expression)
ALIAS(as.expression)
VALUE(
An object with class ``expression'' containing its
unevaluated arguments.  Expression objects are
lists of ``calls'' and so the subsetting operations which apply
to lists also apply to them.  For compatibility with S,
the LANG(mode) function will return LANG("expression")
for expression objects.
PARA
LANG(is.expression) returns LANG(TRUE) if expr is
an expression object and LANG(FALSE) otherwise.
PARA
LANG(as.expression) attempts to coerce its argument
into an expression object.
)
SEEALSO(
LANG(LINK(call)), LANG(LINK(function)).
)
EXAMPLES(
length(ex1 <- expression(1+ 0:9))
ex1
eval(ex1)
)
