Syntactic Sugar for Setting Annotations and Attributes
The operator %#% can be used to attach a
description annotation to an object. %##% can be
used to attach a character vector of annotations to an object.
%@% returns the attribute with the name given as second
argument. With %@% it is also possible to assign attributes.
x %#% descr x %##% annot x %@% nm x %@% nm <- value
x |
an object, usually and |
descr |
a character string |
annot |
a named character vector; its contents are added to the
"annotation" attribute of |
nm |
a character string, the name of the attribute being set or requested. |
value |
any kind of object that can be attached as an attribute. |
test1 <- 1 %#% "One"
# This is equivalent to:
# test <- 1
# description(test) <- "One"
description(test1)
# Results in "One"
# Not that it makes sense, but ...
test2 <- 2 %##% c(
Precedessor = 0,
Successor = 2
)
# This is equivalent to:
# test2 <- 2
# annotation(test2) <- c(
# Precedessor = 0,
# Successor = 2
# )
annotation(test2)
# The following examples are equivalent to
# attr(test2,"annotation")
test2 %@% annotation
test2 %@% "annotation"
test2 %@% another.attribute <- 42
# This is equivalent to attr(test2,"another.attribute") <- 42
attributes(test2)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.