prop: Get/set a property

In S7: An Object Oriented System Meant to Become a Successor to S3 and S4

Get/set a property

Description

• prop(x, "name") / prop@name get the value of the a property, erroring if it the property doesn't exist.

• prop(x, "name") <- value / prop@name <- value set the value of a property.

Usage

prop(object, name)

prop(object, name, check = TRUE) <- value

object@name

Arguments

object	An object from a S7 class
name	The name of the parameter as a character. Partial matching is not performed.
check	If TRUE, check that value is of the correct type and run validate() on the object before returning.
value	A new value for the property. The object is automatically checked for validity after the replacement is done.

Value

prop() and @ return the value of the property. ⁠prop<-()⁠ and ⁠@<-⁠ are called for their side-effects and return the modified object, invisibly.

Examples

Horse <- new_class("Horse", properties = list(
  name = class_character,
  colour = class_character,
  height = class_numeric
))
lexington <- Horse(colour = "bay", height = 15, name = "Lex")
lexington@colour
prop(lexington, "colour")

lexington@height <- 14
prop(lexington, "height") <- 15

S7 documentation built on April 3, 2025, 10:50 p.m.