spsUtil (version 0.2.2)

notFalsy: Judgement of falsy value

Description

judge if an object is or not a falsy value. This includes: empty value, empty string "", NULL, NA, length of 0 and FALSE itself

Usage

notFalsy(x)
isFalsy(x)
emptyIsFalse(x)

Arguments

x

any R object

Value

NA, "", NULL, length(0), nchar == 0 and FALSE will return FALSE, otherwise TRUE in notFalsy and the opposite in isFalsy

Details

R does not have good built-in methods to judge falsy values and these kind of values often cause errors in if conditions, for example if(NULL) 1 else 2 will cause error. So this function will be useful to handle this kind of situations: if(notFalsy(NULL)) 1 else 2.

1. not working on S4 class objects.

2. isFalsy is the reverse of notFalsy: isFalsy(x) = !notFalsy(x)

3. emptyIsFalse is the old name for notFalsy

Useful for if statement. Normal empty object in if will spawn error. Wrap the expression with emptyIsFalse can avoid this. See examples

Examples

# NOT RUN {
notFalsy(NULL)
notFalsy(NA)
notFalsy("")
try(`if(NULL) "not empty" else "empty"`) # this will generate error
if(notFalsy(NULL)) "not falsy" else "falsy" # but this will work
# Similar for `NA`, `""`, `character(0)` and more
isFalsy(NULL)
isFalsy(NA)
isFalsy("")
# }