Check a return parameter from a function

This is intended to be used within a function to check the validity of a data frame being returned from a function against an ispec which is provided.

Usage

ireturn(df, iface, .prune = FALSE)

Arguments

df

a dataframe - if missing then the first parameter of the calling function is assumed to be a dataframe.

iface

the interface specification that df should conform to.

.prune

get rid of excess columns that are not in the spec.

Value

a dataframe based on df with validity checks passed, data-types coerced, and correct grouping applied to conform to iface

Examples

input = iface(col_in = integer ~ "an integer column" )
output = iface(col_out = integer ~ "an integer column" )

x = function(df = input, ...) {
  df = ivalidate(...)
  tmp = df %>% dplyr::rename(col_out = col_in)
  ireturn(tmp, output)
}
x(tibble::tibble(col_in = c(1,2,3)))
#> # A tibble: 3 × 1
#>   col_out
#>     <int>
#> 1       1
#> 2       2
#> 3       3
output
#> A dataframe containing the following columns: 
#> * col_out (integer) - an integer column
#> Any grouping allowed.