Various helpers for using a field name for method dispatch

Given a field as a name, for example "desc", we want to dispatch to the right derivation method for this piece of data. To do this, we need to convert this field name into an object that has a class that we can use for method dispatch. These functions are helpers for standardizing this conversion so that we don't need to concern ourselves with consistent class names throughout this package.

Given a field as a name, for example "name", we want to dispatch to the right derivation method for this piece of data. To do this, we need to convert this field name into an object that has a class that we can use for method dispatch. These functions are helpers for standardizing this conversion so that we don't need to concern ourselves with consistent class names throughout this package.

This is used for finding all available metrics for use in metrics(), as well as for tab completions for <pkg>$ <TAB> to auto-populate a list of available metrics.

Usage

pkg_data_s3_class(field_name = NULL, mock = FALSE)

pkg_data_class(...)

pkg_data_name_from_s3_class(class_name)

as_pkg_data(field_name)

get_data_derive_field_names(..., args = list(...))

Arguments

...

A list of S7::S7_object classes. Not used if args is provided.

args

A list of S7::S7_object classes, by default, collects the elements of ....

Value

A character vector of field names.

Details

In most cases, to dispatch to a method for a field, one would

fn(as_pkg_data("field_name"), ...)

Which creates an S3 object with a corresponding class. For generics in this package that might be dispatched by field name, they often have default methods already implemented so that you can simplify this to:

fn("field_name", ...)

And it will implicitly dispatch to the appropriate method.

In most cases, to dispatch to a method for a field, one would

fn(as_pkg_data("field_name"), ...)

Which creates an S3 object with a corresponding class. For generics in this package that might be dispatched by field name, they often have default methods already implemented so that you can simplify this to:

fn("field_name", ...)

And it will implicitly dispatch to the appropriate method.

Functions

• pkg_data_s3_class(): Convert a field name into an S3 class name for dispatch

• pkg_data_class(): Convert a field name into an S7 S3 class object for dispatch

• pkg_data_name_from_s3_class(): Parse a data field name from its S3 class. The inverse of pkg_data_s3_class.

• as_pkg_data(): Convert a field name an object with appropriate class for dispatch