If-NULL-or-length-is-0: [.] Infix operator %if_null_or_len0%

In GegznaV/spMisc: Infix Operators, Convenience and Other Kind of Miscellaneous Functions

Description

The operator is useful as a way of providing a default value in case the output of another function is NULL or its length is zero.

Usage

a %if_null_or_len0% b

Arguments

a	An expression.
b	An alternative.

Value

If !is.null(a) & length(a) > 0 & nchar(a) > 0 is TRUE returns a, otherwise returns b.

Examples

a1 <- "Default value"
a2 <- NULL
a3 <- character()
b  <- "Alternative"
VECTOR  <- c("Alternative", "Alternative")

 a1 %if_null_or_len0% b
#> [1] "Default value"

 a2 %if_null_or_len0% b
#> "Alternative"

 a3 %if_null_or_len0% b
#> "Alternative"

# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
a1 %if_null_or_len0% VECTOR
#> [1] "Default value"

a2 %if_null_or_len0% VECTOR
#> "Alternative"

VECTOR %if_null_or_len0% a1

GegznaV/spMisc documentation built on April 26, 2020, 5:59 p.m.