JMS #4: Parsing command flags with context

context.go

@@ -0,0 +1,57 @@
+package cli
+
+import (
+	"flag"
+	"strconv"
+)
+
+// Context is a type that is passed through to
+// each Handler action in a cli application. Context
+// can be used to retrieve context-specific Args and
+// parsed command-line options.
+type Context struct {
+	flagSet *flag.FlagSet
+}
+
+func NewContext(flagSet *flag.FlagSet) *Context {
+	return &Context{flagSet}
+}
+
+func (c *Context) IntFlag(name string) int {
+	flag := c.flagSet.Lookup(name)
+	if flag != nil {
+		val, err := strconv.Atoi(flag.Value.String())
+		if err != nil {
+      panic(err)
+		}
+		return val
+	} else {
+		return 0
+	}
+}
+
+func (c *Context) BoolFlag(name string) bool {
+	flag := c.flagSet.Lookup(name)
+	if flag != nil {
+		val, err := strconv.ParseBool(flag.Value.String())
+		if err != nil {
+      panic(err)
+		}
+		return val
+	} else {
+		return false
+	}
+}
+
+func (c *Context) StringFlag(name string) string {
+	flag := c.flagSet.Lookup(name)
+	if flag != nil {
+		return flag.Value.String()
+	} else {
+    return ""
+	}
+}
+
+func (c *Context) Args() []string {
+  return c.flagSet.Args()
+}