Apply Model Modules Using A Simple And Consistent Syntax"
In ready4: Develop and Use Modular Health Economic Models

knitr::opts_chunk$set(echo = TRUE, warning = FALSE)

library(ready4)

Motivation

To be used in health economic analyses, model modules need to be called using a programming syntax. Ideally that syntax should be relatively simple, with the name and description of each command reliably communicating the category of operations it performs.

Implementation

ready4 provides a simple syntax that is used by all model modules developed with the ready4 framework.

Use

A table that itemises ready4 commands along with examples of how these commands are used can be ingested from a periodically updated database using get_methods_tb. In the below example we will search for examples of where that syntax has been used by modules from the readyforwhatsnext model. The value supplied to the gh_repo_1L_chr argument specifies the repository in which a dataset of readyforwhatsnext module libraries is stored.

# Not run
# x <- make_methods_tb(gh_repo_1L_chr = "ready4-dev/ready4")

x <- get_methods_tb(gh_repo_1L_chr = "ready4-dev/ready4")

Core commands

A HTML table of ready4's core commands and examples of the use of each command can be displayed using the print_methods function, using the return_1L_chr = "core" argument.

print_methods(x,
              return_1L_chr = "core",
              scroll_width_1L_chr = "100%")

Applying commands to module "slots"

Each of the "core" commands also has a "slot" version, which applies the command to a specified slot (a named element of a module). Two of these "slot" methods can also be used for additional purposes:

procureSlot is a "getter" method - its default behaviour is to return the value of a specified slot. If the argument use_procure_mthd_1L_lgl = T is included in the method call, procureSlot will instead apply the procure method to a specified slot.
renewSlot is a "setter" method - if any value other than "use_renew_mthd" (the default) is passed to the new_val_xx argument, that value will be assigned to the specified slot.

A HTML table of slot commands and relevant examples can be displayed using the print_methods function, using the return_1L_chr = "slot" argument.

print_methods(x,
              return_1L_chr = "slot",
              scroll_width_1L_chr = "100%")

Extended commands

Finally, there are a small number of other commands that are more general extensions of the core commands. Currently, these extended commands are all variants on the author command, with each extension specifying the type of output to be authored by the method. A HTML table of the extended generics bundled with ready4 can be displayed using the print_methods function, using the return_1L_chr = "extended" argument.

print_methods(x,
              exclude_mthds_for_chr = "Ready4Module",
              return_1L_chr = "extended",
              scroll_width_1L_chr = "100%")