tspec_df: Create a Tibblify Specification

In tibblify: Rectangle Nested Lists

Create a Tibblify Specification

Description

Use tspec_df() to specify how to convert a list of objects to a tibble. Use tspec_row() resp. tspec_object() to specify how to convert an object to a one row tibble resp. a list.

Usage

tspec_df(
  ...,
  .input_form = c("rowmajor", "colmajor"),
  .names_to = NULL,
  vector_allows_empty_list = FALSE
)

tspec_object(
  ...,
  .input_form = c("rowmajor", "colmajor"),
  vector_allows_empty_list = FALSE
)

tspec_recursive(
  ...,
  .children,
  .children_to = .children,
  .input_form = c("rowmajor", "colmajor"),
  vector_allows_empty_list = FALSE
)

tspec_row(
  ...,
  .input_form = c("rowmajor", "colmajor"),
  vector_allows_empty_list = FALSE
)

Arguments

...	Column specification created by tib_*() or tspec_*().
.input_form	The input form of data frame like lists. Can be one of: "rowmajor": The default. The data frame is formed by a list of rows. "colmajor": The data frame is a named list of columns.
.names_to	A string giving the name of the column which will contain the names of elements of the object list. If NULL, the default, no name column is created
vector_allows_empty_list	Should empty lists for input_form = "vector" be accepted and treated as empty vector?
.children	A string giving the name of field that contains the children.
.children_to	A string giving the column name to store the children.

Details

In column major format all fields are required, regardless of the required argument.

Value

A tibblify specification.

Examples

tspec_df(
  id = tib_int("id"),
  name = tib_chr("name"),
  aliases = tib_chr_vec("aliases")
)

# To create multiple columns of the same type use the bang-bang-bang (!!!)
# operator together with `purrr::map()`
tspec_df(
  !!!purrr::map(purrr::set_names(c("id", "age")), tib_int),
  !!!purrr::map(purrr::set_names(c("name", "title")), tib_chr)
)

# The `tspec_*()` functions can also be nested
spec1 <- tspec_object(
  int = tib_int("int"),
  chr = tib_chr("chr")
)
spec2 <- tspec_object(
  int2 = tib_int("int2"),
  chr2 = tib_chr("chr2")
)

tspec_df(spec1, spec2)

tibblify documentation built on Nov. 16, 2022, 5:07 p.m.