knit_child as is

This slightly modifies the knitr::knit_child() function to have different defaults.

• the environment defaults to the calling environment.

• the output receives the class knit_asis, so that the output will be rendered "as is" by knitr when calling inside a chunk (no need to set results='asis' as a chunk option).

• defaults to quiet = TRUE

Usage

asis_knit_child(
  input = NULL,
  text = NULL,
  ...,
  quiet = TRUE,
  options = NULL,
  envir = parent.frame()
)

Arguments

input

if you specify a file path here, it will be read in before being passed to knitr (to avoid a working directory mess)

text

passed to knitr::knit_child()

...

passed to knitr::knit_child()

quiet

passed to knitr::knit_child()

options

defaults to NULL.

envir

passed to knitr::knit_child()

Details

Why default to the calling environment? Typically this function defaults to the global environment. This makes sense if you want to use knit_children in the same context as the rest of the document. However, you may also want to use knit_children inside functions to e.g. summarise a regression using a set of commands (e.g. plot some diagnostic graphs and a summary for a regression nicely formatted).

Some caveats:

• the function has to return to the top-level. There's no way to cat() this from loops or an if-condition without without setting results='asis'. You can however concatenate these objects with paste.knit_asis()

Examples

if (FALSE) { # \dontrun{
# an example of a wrapper function that calls asis_knit_child with an argument
# ensures distinct paths for cache and figures, so that these calls can be looped in parallel
regression_summary = function(model) {
   child_hash = digest::digest(model)
   options = list(
       fig.path = paste0(knitr::opts_chunk$get("fig.path"), child_hash, "-"), 
       cache.path = paste0(knitr::opts_chunk$get("cache.path"), child_hash, "-"))
   asis_knit_child("_regression_summary.Rmd", options = options)
}
} # }