RVerbalExpressions

The goal of RVerbalExpressions is to make it easier to construct regular expressions using grammar and functionality inspired by VerbalExpressions. Usage of %>% is encouraged to build expressions in a chain like fashion.

Installation

Install the released version of RVerbalExpressions from CRAN:

install.packages("RVerbalExpressions")

Or install the development version from GitHub with:

# install.packages("devtools")
devtools::install_github("VerbalExpressions/RVerbalExpressions")

Example

This is a basic example which shows you how to build a regular expression:

library(RVerbalExpressions)

# construct an expression
x <- rx_start_of_line() %>% 
  rx_find('http') %>% 
  rx_maybe('s') %>% 
  rx_find('://') %>% 
  rx_maybe('www.') %>% 
  rx_anything_but(' ') %>% 
  rx_end_of_line()

# print the expression
x
#> [1] "^(http)(s)?(\\://)(www\\.)?([^ ]*)$"

# test for a match
grepl(x, "https://www.google.com")
#> [1] TRUE

Other Implementations

You can see an up to date list of all ports on VerbalExpressions.github.io.

• JavaScript
• Ruby
• C#
• Python
• Java
• Groovy
• PHP
• Haskell
• Haxe
• C++
• Objective-C
• Perl
• Swift

Additionally, there are two R packages that try to solve the same problem. I encourage you to check these out:

1. rex by @kevinushey
2. rebus by @richierocks

Contributing

If you find any issues, typos, etc., please file an issue or submit a PR. All contributions are welcome!