UseFunction: Primary dispatcher for functional programming
In lambda.r: Modeling Data with Functional Programming

Description Usage Arguments Details Value Author(s) See Also Examples

View source: R/framework.R

UseFunction manages the dispatching for multipart functions in lambda.r. This is used internally by lambda.r.

1 2	UseFunction(fn, fn.name, ...) NewObject(type.fn, type.name, ...)

`fn`	The function reference that is being applied
`fn.name`	The name of a function that uses functional dispatching. This is just the name of the function being defined
`type.fn`	The function representing the type constructor
`type.name`	The name of the type
`...`	The arguments that are passed to dispatched functions

This function is used internally and generally does not need to be called by an end user.

Returns the value of the dispatched function

Brian Lee Yung Rowe

%as%

# Note that these are trivial examples for pedagogical purposes. Due to their
# trivial nature, most of these examples can be implemented more concisely
# using built-in R features.


reciprocal(x) %::% numeric : numeric
reciprocal(x) %when% {
  x != 0
} %as% {
  1 / x
}

reciprocal(x) %::% character : numeric
reciprocal(x) %as% {
  reciprocal(as.numeric(x))
}

seal(reciprocal)

print(reciprocal)
reciprocal(4)
reciprocal("4")