From 95009b06b6487db75b7ccd216e34a6f554d90688 Mon Sep 17 00:00:00 2001
From: lilihx <88191432+Lilihx@users.noreply.github.com>
Date: Tue, 5 Jul 2022 20:06:44 +0800
Subject: [PATCH] add flag: -h, --help (#218)

Change-Id: I6d5648b84536c22e518413d0360047431b1acccc
---
 help.go | 1 +
 main.go | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/help.go b/help.go
index 5658c3c..3550ae9 100644
--- a/help.go
+++ b/help.go
@@ -22,6 +22,7 @@ func usage(keyMap KeyMap) string {
     curl ... | fx
 
   %v
+    -h, --help          print help
     -v, --version       print version
     --print-code        print code of the reducer
 
diff --git a/main.go b/main.go
index 2c9b17a..089117e 100644
--- a/main.go
+++ b/main.go
@@ -22,6 +22,7 @@ import (
 )
 
 var (
+	flagHelp      bool
 	flagVersion   bool
 	flagPrintCode bool
 )
@@ -30,6 +31,8 @@ func main() {
 	var args []string
 	for _, arg := range os.Args[1:] {
 		switch arg {
+		case "-h", "--help":
+			flagHelp = true
 		case "-v", "-V", "--version":
 			flagVersion = true
 		case "--print-code":
@@ -39,6 +42,10 @@ func main() {
 		}
 
 	}
+	if flagHelp {
+		fmt.Println(usage(DefaultKeyMap()))
+		return
+	}
 	if flagVersion {
 		fmt.Println(version)
 		return