are_fct_ish: Check if an object can be safely coerced to a factor

In stbl: Stabilize Function Arguments

Check if an object can be safely coerced to a factor

Description

are_fct_ish() is a vectorized predicate function that checks whether each element of its input can be safely coerced to a factor.

is_fct_ish() is a scalar predicate function that checks if all elements of its input can be safely coerced to a factor.

Usage

are_fct_ish(x, ..., levels = NULL, to_na = character())

is_fct_ish(x, ...)

## Default S3 method:
are_fct_ish(x, ..., levels = NULL, to_na = character(), depth = 1)

Arguments

x	The object to check.
...	Arguments passed to methods.
levels	(character) The desired factor levels.
to_na	(character) Values to convert to NA.
depth	⁠(length-1 integer)⁠ Current recursion depth. Do not manually set this parameter.

Value

are_fct_ish() returns a logical vector with the same length as the input. is_fct_ish() returns a ⁠length-1 logical⁠ (TRUE or FALSE) for the entire vector.

Examples

# When `levels` is `NULL`, atomic vectors are fct_ish, but nested lists are not.
are_fct_ish(c("a", 1, NA))
is_fct_ish(c("a", 1, NA))
are_fct_ish(list("a", list("b", "c")))
is_fct_ish(list("a", list("b", "c")))

# When `levels` is specified, values must be in `levels` or `to_na`.
are_fct_ish(c("a", "b", "c"), levels = c("a", "b"))
is_fct_ish(c("a", "b", "c"), levels = c("a", "b"))

# The `to_na` argument allows some values to be treated as `NA`.
are_fct_ish(c("a", "b", "z"), levels = c("a", "b"), to_na = "z")
is_fct_ish(c("a", "b", "z"), levels = c("a", "b"), to_na = "z")

# Factors are also checked against the specified levels.
are_fct_ish(factor(c("a", "b", "c")), levels = c("a", "b"))
is_fct_ish(factor(c("a", "b", "c")), levels = c("a", "b"))

stbl documentation built on Nov. 5, 2025, 6:02 p.m.