diff options
Diffstat (limited to 'go/cmd/command.go')
| -rw-r--r-- | go/cmd/command.go | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/go/cmd/command.go b/go/cmd/command.go new file mode 100644 index 000000000..c8d86ca66 --- /dev/null +++ b/go/cmd/command.go @@ -0,0 +1,54 @@ +package main + +import ( + "flag" + "fmt" + "os" + "strings" +) + +type Command struct { + // Run runs the command. + // The args are the arguments after the command name. + Run func(cmd *Command, args []string) bool + + // UsageLine is the one-line usage message. + // The first word in the line is taken to be the command name. + UsageLine string + + // Short is the short description shown in the 'go help' output. + Short string + + // Long is the long message shown in the 'go help <this-command>' output. + Long string + + // Flag is a set of flags specific to this command. + Flag flag.FlagSet + + IsDebug *bool +} + +// Name returns the command's name: the first word in the usage line. +func (c *Command) Name() string { + name := c.UsageLine + i := strings.Index(name, " ") + if i >= 0 { + name = name[:i] + } + return name +} + +func (c *Command) Usage() { + fmt.Fprintf(os.Stderr, "Example: weed %s\n", c.UsageLine) + fmt.Fprintf(os.Stderr, "Default Usage:\n") + c.Flag.PrintDefaults() + fmt.Fprintf(os.Stderr, "Description:\n") + fmt.Fprintf(os.Stderr, " %s\n", strings.TrimSpace(c.Long)) + os.Exit(2) +} + +// Runnable reports whether the command can be run; otherwise +// it is a documentation pseudo-command such as importpath. +func (c *Command) Runnable() bool { + return c.Run != nil +} |
