model_dashboard: export code used to produce all the outputs

[etiennebacher]

It would be nice to have an additional tab containing code that can simply be copy-pasted in R and produces the same outputs

[etiennebacher]

My bad, I missed the "source code" button

[etiennebacher]

Actually the "source code" button shows the source for the Rmd file, but I was thinking of something like:

# Assumption checks -------------
*Some code here*

# Indices of model fit -------------
*Some code here*

# Tabular summary -------------
*Some code here*

[...]

[IndrajeetPatil]

This should be simple enough. We just need to use knitr::purl():

https://bookdown.org/yihui/rmarkdown-cookbook/purl.html

[etiennebacher]

knitr::purl() extracts the whole chunks, but most of the code there is not needed to reproduce the results (if everything works well).

For example, suppose that there are interactions in the model, then this if condition :

if (is.null(int_terms)) {
  model_terms <- con_terms
} else {
  model_terms <- clean_names(int_terms)
  int_terms <- unique(unlist(strsplit(clean_names(int_terms), ":", fixed = TRUE)))
  model_terms <- c(model_terms, setdiff(con_terms, int_terms))
}

could be reduced to:

model_terms <- clean_names(int_terms)
int_terms <- unique(unlist(strsplit(clean_names(int_terms), ":", fixed = TRUE)))
model_terms <- c(model_terms, setdiff(con_terms, int_terms))

in the exported code.

In the end, I have in mind a text output that doesn't contain any of the conditions/tryCatch that are in the Rmd file, just the code you would run if you had to write it yourself:

params <- list(model = "model", check_model_args = "check_model_args", 
    parameters_args = "parameters_args", performance_args = "performance_args")

#### Assumption checks -----------
do.call(performance::check_model, check_model_args)

#### Indices of model fit -----------
performance_args <- c(list(model), params$performance_args)
# add verbose, if not done yet
if (is.null(performance_args$verbose)) performance_args$verbose <- FALSE
table_performance <- do.call(performance::performance, performance_args)
print_md(table_performance, layout = "vertical", caption = NULL)

...