Added 'flags' to the Compile function, instead of maintaining global state to check whether certain features were enabled

main.go

@@ -10,10 +10,10 @@ import (
 	"github.com/fatih/color"
 )
 
-var notDotChars []rune
-var caseInsensitiveFlag *bool // Whether we are running in case-insensitive mode
-
 func main() {
+	// Flags for the regex Compile function
+	flagsToCompile := make([]ReFlag, 0)
+
 	invertFlag := flag.Bool("v", false, "Invert match.")
 	// This flag has two 'modes':
 	// 1. Without '-v': Prints only matches. Prints a newline after every match.
@@ -22,17 +22,18 @@ func main() {
 	lineFlag := flag.Bool("l", false, "Only print lines with a match (or with no matches, if -v is enabled). Similar to grep's default.")
 	multiLineFlag := flag.Bool("t", false, "Multi-line mode. Treats newline just like any character.")
 	printMatchesFlag := flag.Bool("p", false, "Prints start and end index of each match. Can only be used with '-t' for multi-line mode.")
-	caseInsensitiveFlag = flag.Bool("i", false, "Case-insensitive. Disregard the case of all characters.")
+	caseInsensitiveFlag := flag.Bool("i", false, "Case-insensitive. Disregard the case of all characters.")
+	if *caseInsensitiveFlag {
+		flagsToCompile = append(flagsToCompile, RE_CASE_INSENSITIVE)
+	}
 	matchNum := flag.Int("m", 0, "Print the match with the given index. Eg. -m 3 prints the third match.")
 	substituteText := flag.String("s", "", "Substitute the contents of each match with the given string. Overrides -o and -v")
 	flag.Parse()
 
-	// In multi-line mode, 'dot' metacharacter also matches newline
-	if !(*multiLineFlag) {
-		notDotChars = []rune{'\n'}
-	} else {
-		notDotChars = []rune{}
+	if *multiLineFlag {
+		flagsToCompile = append(flagsToCompile, RE_MULTILINE)
 	}
+
 	// -l and -o are mutually exclusive: -o overrides -l
 	if *onlyFlag {
 		*lineFlag = false
@@ -74,7 +75,7 @@ func main() {
 	reader := bufio.NewReader(os.Stdin)
 	out := bufio.NewWriter(os.Stdout)
 
-	regComp, err := Compile(re)
+	regComp, err := Compile(re, flagsToCompile...)
 	if err != nil {
 		fmt.Println(err)
 		return