Document an interface contract for inserting into roxygen2

This function is expected to be called within the documentation of a function as inline code in the parameter documentation of the function. It details the expected columns that the input dataframe should possess. This has mostly been superseded by the @iparam <name> <description> roxygen2 tag which does this automatically, however in some circumstances (particularly multiple dispatch) you may want to assemble dataframe documentation manually.

Usage

idocument(fn, param = NULL)

Arguments

fn

the function that you are documenting

param

the parameter you are documenting (optional. if missing defaults to the first argument of the function)

Value

a markdown snippet

Examples

#' @param df `r idocument(x, df)`
x = function(df = iface( col1 = integer ~ "an integer column" )) {}

cat(idocument(x, df))
#> A dataframe containing the following columns: 
#> 
#> * col1 (integer) - an integer column
#> 
#> Any grouping allowed.