Multiline descriptions and help messages

examples/multiline/multiline.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/akamensky/argparse"
+)
+
+func main() {
+	// Create new parser object
+	parser := argparse.NewParser("help",
+		`Demonstrates multiline description and help messages.
+With some very long lines like this one which is broken automatically by argparse.
+And some shorter.`)
+	// Create string flag
+	parser.String("s", "string", &argparse.Options{Required: true, Help: "String argument example\non several lines"})
+	// Create string flag
+	parser.Int("i", "int", &argparse.Options{Required: true, Help: "Integer argument example"})
+	// Use the help function
+	fmt.Print(parser.Help(nil))
+}

extras.go

@@ -8,6 +8,21 @@ func getLastLine(input string) string {
 }
 
 func addToLastLine(base string, add string, width int, padding int, canSplit bool) string {
+	// Split the multiline string to add
+	if strings.Contains(add, "\n") {
+		lines := strings.Split(add, "\n")
+		firstLine := true
+		for _, v := range lines {
+			if firstLine {
+				base = addToLastLine(base, v, width, padding, true)
+				firstLine = false
+			} else {
+				base = base + "\n" + strings.Repeat(" ", padding)
+				base = addToLastLine(base, v, width, padding, true)
+			}
+		}
+		return base
+	}
 	// If last line has less than 10% space left, do not try to fill in by splitting else just try to split
 	hasTen := (width - len(getLastLine(base))) > width/10
 	if len(getLastLine(base)+" "+add) >= width {