Package {structenforcement}

Title: Struct-Like Data Type Checking and Enforcement
Version: 0.3.0
Description: Enforcement of field types in lists. A drop-in tool to allow for dynamic input data that might be questionably parsed or cast to be coerced into the specific desired format in a reasonably performant manner.
License: MIT + file LICENSE
Encoding: UTF-8
RoxygenNote: 7.3.3
Suggests: lubridate, testthat (≥ 3.0.0)
Config/testthat/edition: 3
Imports: rlang
NeedsCompilation: yes
Packaged: 2026-06-30 06:32:43 UTC; yakumo
Author: Samuel Sapire [aut, cre, cph], Sean Barrett [ctb]
Maintainer: Samuel Sapire <sapires@protonmail.com>
Repository: CRAN
Date/Publication: 2026-06-30 06:50:02 UTC

Bind as Struct

Description

Given a set of lists/dataframes, attempt to join them as a dataframe with field types matching the specified template. The default approach uses all fields present in the input lists, while the strict mode ensures that the template fields and only the template fields are present.

Usage

bind_as_struct(template, ..., .list = NULL, strict = FALSE)

Arguments

template

A named list to use as a template.

...

The lists to join

.list

A pre-built list of frames to join, as an alternative to .... Use exactly one of ... or .list.

strict

Use all and only the fields in the template. Default: FALSE

Value

A dataframe containing the combined inputs.

Examples

bind_as_struct(list("a" = character(0)), list("a" = 1), list("a" = "a"))

List Type Checking

Description

Given two named objects, go through both and make the types of the second match the types of the first.

Usage

type_check(
  template,
  target,
  with_cast = FALSE,
  log_items = c("casts", "missing", "excess", "debug")[c(1, 3)]
)

Arguments

template

  • A named list to use as a template.

target

  • A named list to use as the output.

with_cast

  • If true, edits the target instead of just checking types.

log_items

  • Which debug info to print. Takes a character vector. By default, logs casts and excess fields (target fields not in template). We expect some missing for the moment.

Value

The target object, with its types appropriately cast.

Examples

type_check(
  list("a" = character(0), "b" = integer(0)),
  data.frame("a" = c(1,2), "b" = c(3,4)),
  TRUE, NULL
)

Vectorised List Type Checking

Description

Apply type_check to each element in a list of targets against a single template. The template lookup table is built once and reused across every target, amortising the hash-table construction.

Usage

type_check_each(
  template,
  targets,
  with_cast = FALSE,
  log_items = c("casts", "missing", "excess", "debug")[c(1, 3)]
)

Arguments

template

A named list to use as a template.

targets

A list of named lists/dataframes to check against the template.

with_cast

If true, edits each target instead of just checking types.

log_items

Which debug info to print. Mirrors type_check.

Value

A list of the targets, with their types appropriately cast. Names of targets are preserved.

Examples

type_check_each(
  list("a" = character(0), "b" = integer(0)),
  list(list("a" = 1, "b" = 2.5), list("a" = "x", "b" = 3L)),
  TRUE, NULL
)