cmd pkg for Subcommand type, use everywhere

cmd/cmd.go

@@ -0,0 +1,11 @@
+package cmd
+
+type Subcommand string
+
+const (
+	Tag  Subcommand = "tag"
+	Next Subcommand = "next"
+	Last Subcommand = "last"
+	Sort Subcommand = "sort"
+	Help Subcommand = "help"
+)

flags/flags.go

@@ -7,6 +7,8 @@ import (
 	"reflect"
 	"strings"
 	"text/tabwriter"
+
+	"github.com/brtholomy/um/go/cmd"
 )
 
 type Arg struct {
@@ -74,17 +76,17 @@ func ValidateIncrementFetchOrExit(args []string, i int) (int, string) {
 	return i + 1, args[i+1]
 }
 
-func HelpRequired(cmd string, long string) {
-	log.Printf("um %s: %s is required", cmd, long)
+func HelpRequired(sub cmd.Subcommand, long string) {
+	log.Printf("um %s: %s is required", sub, long)
 }
 
-func HelpInvalidArg(cmd string, arg string) {
-	log.Printf("um %s: invalid argument: %s", cmd, arg)
+func HelpInvalidArg(sub cmd.Subcommand, arg string) {
+	log.Printf("um %s: invalid argument: %s", sub, arg)
 }
 
 // print out help string by reflecting over fields of provided opts struct
 // and os.Exit(0)
-func Help(subcmd string, opts any) {
+func Help(sub cmd.Subcommand, opts any) {
 	v := reflect.ValueOf(opts)
 	t := v.Type()
 
@@ -110,7 +112,7 @@ func Help(subcmd string, opts any) {
 			)
 		}
 	}
-	log.Printf("um %s%s\n", subcmd, positional)
+	log.Printf("um %s%s\n", sub, positional)
 	w.Flush()
 	os.Exit(0)
 }

next/last.go

@@ -8,10 +8,9 @@ import (
 	"os/exec"
 	"regexp"
 	"strings"
-)
 
-// but this stinks:
-const lcmd = "last"
+	cmdpkg "github.com/brtholomy/um/go/cmd"
+)
 
 const (
 	// NOTE: the -r flag:
@@ -47,7 +46,7 @@ func last() (string, error) {
 func Last() {
 	s, err := last()
 	if err != nil {
-		log.Fatalf("um %s: %v", lcmd, err)
+		log.Fatalf("um %s: %v", cmdpkg.Last, err)
 	}
 	// send to stdout, not stderr as is default for log.Print:
 	fmt.Println(s)

next/next.go

@@ -7,10 +7,11 @@ import (
 	"os/exec"
 	"strconv"
 
+	cmdpkg "github.com/brtholomy/um/go/cmd"
 	"github.com/brtholomy/um/go/flags"
 )
 
-const cmd = "next"
+const this = cmdpkg.Next
 
 type options struct {
 	Descriptor flags.Arg
@@ -35,10 +36,10 @@ func parseArgs(args []string) options {
 		case i == 1 && !flags.HasDashPrefix(arg):
 			opts.Tags.Val = arg
 		case arg == opts.Help.Long || arg == opts.Help.Short:
-			flags.Help(cmd, opts)
+			flags.Help(this, opts)
 		default:
-			flags.HelpInvalidArg(cmd, arg)
-			flags.Help(cmd, opts)
+			flags.HelpInvalidArg(this, arg)
+			flags.Help(this, opts)
 		}
 	}
 	return opts
@@ -109,13 +110,13 @@ func Next(args []string) {
 	opts := parseArgs(args)
 	l, err := last()
 	if err != nil {
-		log.Fatalf("um %s: %v", cmd, err)
+		log.Fatalf("um %s: %v", this, err)
 	}
 	filename, err := next(l, opts.Descriptor.Val)
 	if err != nil {
-		log.Fatalf("um %s: %v", cmd, err)
+		log.Fatalf("um %s: %v", this, err)
 	}
 	if err := emacsNext(filename, opts.Tags.Val); err != nil {
-		log.Fatalf("um %s: %v", cmd, err)
+		log.Fatalf("um %s: %v", this, err)
 	}
 }

sort/sort.go

@@ -7,11 +7,12 @@ import (
 	"slices"
 	"strings"
 
+	cmdpkg "github.com/brtholomy/um/go/cmd"
 	"github.com/brtholomy/um/go/flags"
 	"github.com/brtholomy/um/go/pipe"
 )
 
-const cmd = "sort"
+const cmd = cmdpkg.Sort
 
 type options struct {
 	Source flags.Flag[string]
@@ -43,7 +44,7 @@ func parseArgs(args []string) options {
 		case arg == opts.Help.Long || arg == opts.Help.Short:
 			flags.Help(cmd, opts)
 		default:
-			log.Printf("um sort: invalid argument: %s", arg)
+			flags.HelpInvalidArg(cmd, arg)
 			flags.Help(cmd, opts)
 		}
 	}

tag/tag.go

@@ -3,10 +3,12 @@ package tag
 import (
 	"log"
 
+	cmdpkg "github.com/brtholomy/um/go/cmd"
 	"github.com/brtholomy/um/go/flags"
 )
 
-const cmd = "tag"
+// just so that copied calls into flags.Help don't have to be adjusted between files:
+const cmd = cmdpkg.Tag
 
 type options struct {
 	Query   flags.Arg

um.go

@@ -5,22 +5,13 @@ import (
 	"log"
 	"os"
 
-	nextpkg "github.com/brtholomy/um/go/next"
-	sortpkg "github.com/brtholomy/um/go/sort"
-	tagpkg "github.com/brtholomy/um/go/tag"
+	"github.com/brtholomy/um/go/cmd"
+	"github.com/brtholomy/um/go/next"
+	"github.com/brtholomy/um/go/sort"
+	"github.com/brtholomy/um/go/tag"
 )
 
-type Subcommand string
-
-const (
-	tag  Subcommand = "tag"
-	next Subcommand = "next"
-	last Subcommand = "last"
-	sort Subcommand = "sort"
-	help Subcommand = "help"
-)
-
-var helpShort string = fmt.Sprintf("um [%s | %s | %s | %s | %s]", tag, next, last, sort, help)
+var helpShort string = fmt.Sprintf("um [%s | %s | %s | %s | %s]", cmd.Tag, cmd.Next, cmd.Last, cmd.Sort, cmd.Help)
 var helpLong string = fmt.Sprintf(`%s
 
 An (U)ltralight database for (M)arkdown composition.
@@ -40,19 +31,19 @@ func main() {
 		log.Fatalln(helpShort)
 	}
 
-	cmd := Subcommand(os.Args[1])
+	arg := cmd.Subcommand(os.Args[1])
 	args := os.Args[2:]
 
-	switch cmd {
-	case next:
-		nextpkg.Next(args)
-	case last:
-		nextpkg.Last()
-	case tag:
-		tagpkg.Tag(args)
-	case sort:
-		sortpkg.Sort(args)
-	case help:
+	switch arg {
+	case cmd.Next:
+		next.Next(args)
+	case cmd.Last:
+		next.Last()
+	case cmd.Tag:
+		tag.Tag(args)
+	case cmd.Sort:
+		sort.Sort(args)
+	case cmd.Help:
 		log.Fatalln(helpLong)
 	default:
 		log.Println("um: command not found")