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Create a tibblify specification

Source: R/tspec.R
tspec_df.Rd

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

Usage

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

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

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

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

Arguments

...

(tib_collector or tspec) Column specifications created by tib_*() or tspec_*(). If the dots are named, the name will be used for the resulting column. Otherwise, the name of the input will be used for the column name.

.input_form

(character(1)) The input form of data-frame-like lists. Can be one of:

  • "rowmajor": The default. The input is a named list of rows.

  • "colmajor": The input is a named list of columns.

.names_to

(character(1) or NULL) The name of the column in the output which will contain the names of top-level elements of the input named list. If NULL, the default, no name column is created.

.vector_allows_empty_list, vector_allows_empty_list

(logical(1)) Should empty lists for columns with .input_form = "vector" be accepted and treated as empty vectors?

.children

(character(1)) The name of the field that contains the children.

.children_to

(character(1)) The column name in which to store the children.

Value

A tibblify specification.

Details

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

Examples

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

# Equivalent to
tspec_df(
  tib_int("id"),
  tib_chr("name"),
  tib_chr_vec("aliases")
)
#> tspec_df(
#>   tib_int("id"),
#>   tib_chr("name"),
#>   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(rlang::set_names(c("id", "age")), tib_int),
  !!!purrr::map(rlang::set_names(c("name", "title")), tib_chr)
)
#> tspec_df(
#>   tib_int("id"),
#>   tib_int("age"),
#>   tib_chr("name"),
#>   tib_chr("title"),
#> )

# 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)
#> tspec_df(
#>   tib_int("int"),
#>   tib_chr("chr"),
#>   tib_int("int2"),
#>   tib_chr("chr2"),
#> )