grade_learnr: A checker function to use with 'learnr'

In cgamboasanabria/gradethis: Tools for "grading" student exercises in learnr tutorials

Description

For exercise checking, learnr tutorials require a function that learnr can use in the background to run the code in each "-check" chunk and to format the results into a format that learnr can display. The function must accept a specific set of inputs and return a specific type of output (see graded()). Instructors are not intended to use the grade_learnr function directly, but to pass it to the exercise.checker knitr chunk option within the setup chunk of the learnr tutorial.

Usage

grade_learnr(label = NULL, solution_code = NULL, user_code = NULL,
  check_code = NULL, envir_result = NULL, evaluate_result = NULL,
  envir_prep = NULL, last_value = NULL, ...)

Arguments

label	Label for exercise chunk
solution_code	Code provided within the “-solution” chunk for the exercise.
user_code	R code submitted by the user
check_code	Code provided within the “-check” chunk for the exercise.
envir_result	The R environment after the execution of the chunk.
evaluate_result	The return value from the evaluate::evaluate function.
envir_prep	A copy of the R environment before the execution of the chunk.
last_value	The last value from evaluating the exercise.
...	Extra arguments supplied by learnr

Details

To enable exercise checking in your learnr tutorial, set tutorial_options(exercise.checker = grade_learnr) in the setup chunk of your tutorial.

Run gradethis_demo() to see an example learnr document that uses grade_learnr().

Value

An R list which contains several fields indicating the result of the check.

Examples

## Not run: gradethis_demo()

cgamboasanabria/gradethis documentation built on June 11, 2020, 12:15 a.m.