Skip to contents

Reduce binary predicate over a list

reduce_predicate.Rd

This function applies a binary predicate function .f over a list .l, checking if the result is TRUE for any or all ordered pairs within .l.

accumulate_predicate() is similar, but returns a logical vector of the accumulated results of the tests.

Usage

reduce_predicate(.l, .f, ..., .op = "or")

accumulate_predicate(.l, .f, ..., .op = "or")

Arguments

.l

[list()] A list of objects to compare.

.f

[function()] A binary predicate function, that uses their first two arguments for the operation, and returns a single TRUE or FALSE.

...

Additional arguments passed to .f.

.op

["or" | "and"] Whether to check if the predicate is TRUE for any or any or all ordered pairs within .l.

Value

  • [TRUE | FALSE | NA] For reduce_predicate(): the scalar reduced result.

  • [logical(length(.l) - 1)] For accumulate_predicate(): the accumulated results.

Examples

reduce_predicate(list(1L, 1.0, 3), `==`, .op = "or") #> TRUE
#> [1] TRUE
reduce_predicate(list(1L, 1.0, 3), `==`, .op = "and") #> FALSE
#> [1] FALSE

accumulate_predicate(list(1L, 1.0, 3), `==`, .op = "and") #> c(TRUE, FALSE)
#> [1]  TRUE FALSE
accumulate_predicate(list(1L, 1.0, 3), identical, .op = "and") #> c(FALSE, FALSE)
#> [1] FALSE FALSE