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Combine strings using builtin infix operators.

remotes::install_github("traversc/stringplus")

Using the& operator concatenates two strings.

"hello" & "world"# output: "helloworld"

Using the| operator formats a string usingsprintf orglue::glue depending on whether the second argument is named.

# Using sprintf"C:/folder/%s/file.txt" | "subfolder"# Using glue::glue"C:/folder/{var}/file.txt" | c(var="subfolder")# Output: "C:/folder/subfolder/file.txt"

You can change the infix operators in the above examples by callingset_string_ops.

set_string_ops(concat = "+", format = "*", permanent = FALSE)"hello" + "world"# output: "helloworld""C:/folder/%s/file.txt" * "subfolder"# Output: "C:/folder/subfolder/file.txt"

Settingpermanent = TRUE will make these settings persist between sessions.

Many infix operators in base R functions are hard coded to return an error on character vector inputs.This is unlike the behavior for custom classes, where they can be modified using the R dispatch system.

While these operators can't be modified for string input, they CAN be overwritten. Instringplus, the built-in operators are overwritten to check if the first argument is a character vector; if so it concatenates (or formats) the two arguments, if not it falls back to the built-in operator.

This overridden function should not interfere with normal dispatch.

set_string_ops(concat = "+", format = "*", permanent = FALSE)library(ggplot2)ggplot(mtcars, aes(x = mpg, y = cyl)) + geom_point()1 + 2 # output: 31 * 2 # output: 2setClass("Zoo", slots=list(animals="numeric"))setMethod("+", signature = c("Zoo", "Zoo"),          function(e1, e2) new("Zoo", animals=e1@animals + e2@animals))sandiego <- new("Zoo", animals=4000)columbus <- new("Zoo", animals=7000)sandiego + columbus# Output# An object of class "Zoo"# Slot "animals":# [1] 11000

Isn't there a performance cost?

• Yes, there is a small performance cost around 1-2 microsecond per op

Wouldn't this interfere with class dispatch methods?

• No, see examples

Could this break something else?

• I don't think so, please let me know if you can think of a way it does!