VM Regex Engine(in Golang)

This is simple VM regex engine written in Go.

Description

This engine may not be practical as I just wrote this to learn how the dfa engine works.

Metacharacters

The engine supports the following metacharacters.

Metacharacter	Desciption	Examples
.	Matches any characters.	. = a, b, c
*	Matches 0 or more repetitions of a pattern.	a* = a, aaa...
+	Matches 1 or more repetitions of a pattern.	(abc)+ = abc, abcabc, abcabcabc...
?	Matches 0 or 1 repetitions of a pattern.	Apple? = Appl, Apple
\|	Match any of the left and right patterns.(like the Boolean OR)	a\|b\|c = a, b, c

Usage

re := vmregex.Compile("(a|b)c*")
re.Match("acccc")   // => true

Example

package main

import (
	"fmt"
	"github.com/8ayac/vm-regex-engine/vmregex"
)

func main() {
	regex := "piyo(o*)"
	re := vmregex.Compile(regex)

	for _, s := range []string{"piyo", "piyoooo", "piy0"} {
		if re.Match(s) {
			fmt.Printf("%s\t=> matched.\n", s)
		} else {
			fmt.Printf("%s\t=> NOT matched.\n", s)
		}
	}
}

$ go run main.go
piyo	=> matched.
piyoooo	=> matched.
piy0	=> NOT matched.

How to install

$ go get -u github.com/8ayac/vm-regex-engine

License

MIT

Author

8ayac