In VerbalExpressions/RVerbalExpressions: Create Regular Expressions Easily

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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

# test for a match
grepl(x, "https://www.google.com")