quotes

What it does

Checks for consistency of quote delimiters in string literals. This rule is disabled by default.

Why is this bad?

In general, single (') and double (") quotes can be used interchangeably within R. However, inconsistent use of quote styles decreases readability.

Base R documentation and the Tidyverse style guide recommend using double quotes for all strings, except for when the string already contains double quotes. Therefore, by default, this rule expects double quotes (").

To prefer single quotes, set this in jarl.toml:

[lint.quotes]
quote = "single"

For regular strings, this rule allows the opposite quote when needed to avoid escaping the preferred quote. For example,

cat('R says "Hello world" ...')

is easier to read than

cat("R says \"Hello world\" ...")

Raw strings also allow the use of the opposite quote for readability and to prevent early termination.

For example:

r'("rawstring")'

is more readable than

r"("rawstring")"

Using the wrong delimiter can also terminate the string early. For example:

r'(abc)"def)'

is valid R, but

r"(abc)"def)"

results in early termination and a syntax error.

Example

x <- 'hello'
print(r'-('hello')-')

Use instead:

x <- "hello"
print(r"-('hello')-")

References

See:

• Tidyverse style guide
• R documentation