BaseTask (Abstract Base Class)

An abstract base class for all task classes. It defines the task name, input/output schema, a pre-filtering hook, and the main processing interface.

Public fields

task_name

Name of the task

input_schema

Named list specifying the expected input structure (field name -> type)

output_schema

Named list specifying the expected output structure (field name -> type)

Methods

Public methods

• BaseTask$new()

• BaseTask$pre_filter()

• BaseTask$call()

• BaseTask$clone()

---

Method new()

Initialize the task instance. Can be overridden in subclasses.

Usage

BaseTask$new(task_name = NULL, input_schema = NULL, output_schema = NULL)

Arguments

task_name

A string specifying the name of the task.

input_schema

A named list describing the input data schema (optional).

output_schema

A named list describing the output data schema (optional).

---

Method pre_filter()

Pre-filter hook to modify or filter the input data before main processing.

Usage

BaseTask$pre_filter(df)

Arguments

df

A data frame or lazy data object (e.g., from dplyr or data.table).

Returns

A filtered or modified version of the input data.

---

Method call()

Main processing function. Must be overridden in subclasses.

Usage

BaseTask$call(patient)

Arguments

patient

A list or structured object representing a single patient or record.

Returns

A list of named lists (equivalent to Python ListDict) representing the task result.

---

Method clone()

The objects of this class are cloneable with this method.

Usage

BaseTask$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.