.gitignore

@@ -1 +1,2 @@
-kg/kg
+re
+

Makefile

@@ -5,13 +5,9 @@ fmt:
 	go fmt ./...
 vet: fmt
 	go vet ./...
-buildLibUnopt: vet
-	go build -gcflags="all=-N -l" ./...
-unopt: buildLibUnopt
-	go build -C kg/ -gcflags="all=-N -l" -o kg ./...
 buildLib: vet
-	go build ./...
+	go build -gcflags="all=-N -l" ./...
 buildCmd: buildLib
-	go build -C kg/ -o kg ./...
+	go build -C cmd/ -gcflags="all=-N -l" -o re ./...
 test: buildCmd
 	go test -v ./...

README.md

@@ -15,7 +15,3 @@ It also includes features not present in regexp, such as lookarounds and backref
 The syntax is, for the most part, a superset of Go's regexp. A full overview of the syntax can be found [here](https://pkg.go.dev/gitea.twomorecents.org/Rockingcool/kleingrep/regex#hdr-Syntax).
 
 __For more information, see https://pkg.go.dev/gitea.twomorecents.org/Rockingcool/kleingrep/regex__.
-
-### How it works
-
-I've written about the inner workings of the engine [on my blog](https://twomorecents.org/writing-regex-engine/index.html).

cmd/helpers.go

@@ -1,11 +1,6 @@
 package main
 
-import (
-	"bufio"
-	"os"
-	"slices"
-	"strings"
-)
+import "slices"
 
 type character interface {
 	int | rune
@@ -30,23 +25,3 @@ func genRange[T character](start, end T) []T {
 	}
 	return toRet
 }
-
-// Returns whether or not the given file contains a NULL character
-func fileContainsNullChar(filename string) (bool, error) {
-	file, err := os.Open(filename)
-	if err != nil {
-		return true, err
-	}
-	defer file.Close()
-	scanner := bufio.NewScanner(file)
-	for scanner.Scan() {
-		line := scanner.Text()
-		if strings.Contains(line, "\000") {
-			return true, nil
-		}
-	}
-	if err := scanner.Err(); err != nil {
-		return true, err
-	}
-	return false, nil
-}

cmd/main.go

@@ -91,7 +91,6 @@ func main() {
 		inputFilenames := flag.Args()[1:]
 		for _, inputFilename := range inputFilenames {
 			inputFile, err := os.Open(inputFilename)
-			defer inputFile.Close()
 			if err != nil {
 				fmt.Printf("%s: %s: No such file or directory\n", os.Args[0], inputFilename)
 			} else {
@@ -103,25 +102,12 @@ func main() {
 					if fileStat.Mode().IsDir() {
 						fmt.Printf("%s: %s: Is a directory\n", os.Args[0], inputFilename)
 					} else {
-						var nullCharPresent bool
-						if nullCharPresent, err = fileContainsNullChar(inputFilename); nullCharPresent {
-							if err != nil {
-								fmt.Printf("%v\n", err)
-								os.Exit(1)
-							} else {
-								fmt.Printf("%s: %s: Is a binary file\n", os.Args[0], inputFilename)
-							}
-						} else {
-							inputFiles = append(inputFiles, inputFile)
-						}
+						inputFiles = append(inputFiles, inputFile)
 					}
 				}
 			}
 		}
 	}
-	if len(inputFiles) == 0 { // No valid files given
-		os.Exit(2)
-	}
 
 	var test_str string
 	var err error

regex/postfixNode.go

@@ -131,9 +131,13 @@ func newEscapedNode(c rune, inCharClass bool) (postfixNode, error) {
 	case 'v': // Vertical tab
 		toReturn.nodetype = characterNode
 		toReturn.contents = append(toReturn.contents, rune(11))
-	case '-': // Literal hyphen
-		toReturn.nodetype = characterNode
-		toReturn.contents = append(toReturn.contents, '-')
+	case '-': // Literal hyphen - only in character class
+		if inCharClass {
+			toReturn.nodetype = characterNode
+			toReturn.contents = append(toReturn.contents, '-')
+		} else {
+			return postfixNode{}, fmt.Errorf("invalid escape character")
+		}
 	default: // None of the above - append it as a regular character
 		if isNormalChar(c) { // Normal characters cannot be escaped
 			return postfixNode{}, fmt.Errorf("invalid escape character")