Coerce to a promise

Use is.promise to determine whether an R object is a promise. Use as.promise (an S3 generic method) to attempt to coerce an R object to a promise, and is.promising (another S3 generic method) to test whether as.promise is supported. mirai::mirai objects have an as.promise method defined in the mirai package, and this package provides one for converting future::Future objects into promises.

Usage

is.promise(x)

is.promising(x)

as.promise(x)

Arguments

x

An R object to test or coerce.

Value

as.promise returns a promise object, or throws an error if the object cannot be converted.

is.promise returns TRUE if the given value is a promise object, and FALSE otherwise.

is.promising returns TRUE if the given value is a promise object or if it can be converted to a promise object using as.promise, and FALSE otherwise.