Precondition: Constructor of the class Precondition

In cartowong/oo: Object-oriented framework for R programming

Description

Utility functions for checking the type of an argument, based on TypeChecker in the same package. If the argument is not of the expected type, an error will be thrown. Usually, these utility functions are called at the begining of a function body.

Usage

Precondition(allowNA = FALSE, allowNull = FALSE)

Arguments

allowNA	Should NA be allowed? The method checkIsNull ignores this parameter.
allowNull	Should NULL be allowed? The method checkIsNA ignores this parameter.

Value

an instance of Precondition

Examples

precondition <- Precondition()
myFunction <- function(x) {
  precondition$isNumeric(x, 'x should be numeric')
  ...
}

cartowong/oo documentation built on May 21, 2019, 2:21 p.m.