The goal of inferregex is to infer the regular expression (regex)–along with other features–of a string.
You can install inferregex from GitHub with:
remotes::install_github("daranzolin/inferregex")library(inferregex)
s <- "abcd-9999-ab9"
infer_regex(s)$regex
#> [1] "^[a-z]{4}-\\d{4}-[a-z]{2}\\d$"library(purrr)
(regex_df <- map_dfr(rownames(mtcars), infer_regex))
#> string regex
#> 1 Mazda RX4 ^[A-Z][a-z]{4}\\s[A-Z]{2}\\d$
#> 2 Mazda RX4 Wag ^[A-Z][a-z]{4}\\s[A-Z]{2}\\d\\s[A-Z][a-z]{2}$
#> 3 Datsun 710 ^[A-Z][a-z]{5}\\s\\d{3}$
#> 4 Hornet 4 Drive ^[A-Z][a-z]{5}\\s\\d\\s[A-Z][a-z]{4}$
#> 5 Hornet Sportabout ^[A-Z][a-z]{5}\\s[A-Z][a-z]{9}$
#> 6 Valiant ^[A-Z][a-z]{6}$
#> 7 Duster 360 ^[A-Z][a-z]{5}\\s\\d{3}$
#> 8 Merc 240D ^[A-Z][a-z]{3}\\s\\d{3}[A-Z]$
#> 9 Merc 230 ^[A-Z][a-z]{3}\\s\\d{3}$
#> 10 Merc 280 ^[A-Z][a-z]{3}\\s\\d{3}$
#> 11 Merc 280C ^[A-Z][a-z]{3}\\s\\d{3}[A-Z]$
#> 12 Merc 450SE ^[A-Z][a-z]{3}\\s\\d{3}[A-Z]{2}$
#> 13 Merc 450SL ^[A-Z][a-z]{3}\\s\\d{3}[A-Z]{2}$
#> 14 Merc 450SLC ^[A-Z][a-z]{3}\\s\\d{3}[A-Z]{3}$
#> 15 Cadillac Fleetwood ^[A-Z][a-z]{7}\\s[A-Z][a-z]{8}$
#> 16 Lincoln Continental ^[A-Z][a-z]{6}\\s[A-Z][a-z]{10}$
#> 17 Chrysler Imperial ^[A-Z][a-z]{7}\\s[A-Z][a-z]{7}$
#> 18 Fiat 128 ^[A-Z][a-z]{3}\\s\\d{3}$
#> 19 Honda Civic ^[A-Z][a-z]{4}\\s[A-Z][a-z]{4}$
#> 20 Toyota Corolla ^[A-Z][a-z]{5}\\s[A-Z][a-z]{6}$
#> 21 Toyota Corona ^[A-Z][a-z]{5}\\s[A-Z][a-z]{5}$
#> 22 Dodge Challenger ^[A-Z][a-z]{4}\\s[A-Z][a-z]{9}$
#> 23 AMC Javelin ^[A-Z]{3}\\s[A-Z][a-z]{6}$
#> 24 Camaro Z28 ^[A-Z][a-z]{5}\\s[A-Z]\\d{2}$
#> 25 Pontiac Firebird ^[A-Z][a-z]{6}\\s[A-Z][a-z]{7}$
#> 26 Fiat X1-9 ^[A-Z][a-z]{3}\\s[A-Z]\\d-\\d$
#> 27 Porsche 914-2 ^[A-Z][a-z]{6}\\s\\d{3}-\\d$
#> 28 Lotus Europa ^[A-Z][a-z]{4}\\s[A-Z][a-z]{5}$
#> 29 Ford Pantera L ^[A-Z][a-z]{3}\\s[A-Z][a-z]{6}\\s[A-Z]$
#> 30 Ferrari Dino ^[A-Z][a-z]{6}\\s[A-Z][a-z]{3}$
#> 31 Maserati Bora ^[A-Z][a-z]{7}\\s[A-Z][a-z]{3}$
#> 32 Volvo 142E ^[A-Z][a-z]{4}\\s\\d{3}[A-Z]$
#> nchars nlower nupper ndigits nwhite
#> 1 9 4 3 1 1
#> 2 13 6 4 1 2
#> 3 10 5 1 3 1
#> 4 14 9 2 1 2
#> 5 17 14 2 0 1
#> 6 7 6 1 0 0
#> 7 10 5 1 3 1
#> 8 9 3 2 3 1
#> 9 8 3 1 3 1
#> 10 8 3 1 3 1
#> 11 9 3 2 3 1
#> 12 10 3 3 3 1
#> 13 10 3 3 3 1
#> 14 11 3 4 3 1
#> 15 18 15 2 0 1
#> 16 19 16 2 0 1
#> 17 17 14 2 0 1
#> 18 8 3 1 3 1
#> 19 11 8 2 0 1
#> 20 14 11 2 0 1
#> 21 13 10 2 0 1
#> 22 16 13 2 0 1
#> 23 11 6 4 0 1
#> 24 10 5 2 2 1
#> 25 16 13 2 0 1
#> 26 9 3 2 2 1
#> 27 13 6 1 4 1
#> 28 12 9 2 0 1
#> 29 14 9 3 0 2
#> 30 12 9 2 0 1
#> 31 13 10 2 0 1
#> 32 10 4 2 3 1
all(map2_lgl(regex_df$string, regex_df$regex, ~grepl(.y, .x)))
#> [1] TRUE