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.
Additionally, there are two R packages that try to solve the same
problem. I encourage you to check these out:
- rex by
@kevinushey - rebus by
@richierocks
Contributing
If you find any issues, typos, etc., please file an issue or submit a
PR. All contributions are welcome!