Validate Named Fields of a List

Applies a different validator to each named element of a list, for heterogeneous configuration or argument lists. Errors carry the field path, e.g. opts$alpha.

Usage

require_fields(restriction, ..., .required = TRUE)

Arguments

restriction

a restriction object.

...

named restriction objects, one per field.

.required

logical; if TRUE (default) a missing field is a failure. If FALSE, a missing field passes. A field whose validator allows NULL (see allow_null()) may always be missing.

Value

The modified restriction object.

See also

Other composition: allow_null(), require_any(), require_col(), require_each(), require_valid()

Examples

opts_v <- restrict("opts") |>
  require_class("list") |>
  require_fields(
    alpha = restrict("alpha") |> require_numeric() |> require_between(0, 1),
    label = restrict("label") |> require_character()
  )
opts_v(list(alpha = 0.05, label = "a"))
validation_errors(opts_v, list(alpha = 2))
#> [1] "opts$alpha: must be in [0, 1]\n  Found: 2"
#> [2] "opts$label: is required but missing"