nicer but my fsm is wrong if i want to bundle ands first

cmd/cli/query.go

@@ -2,7 +2,7 @@ package cli
 
 import (
 	"fmt"
-	"io"
+	"log"
 
 	"gogs.inhome.blapointe.com/ana-ledger/src/ledger"
 )
@@ -10,67 +10,91 @@ import (
 type Query struct{}
 
 func BuildQuery(args args) (ledger.Like, error) {
-	likes := make(ledger.Likes, 0)
-
-	for _, ok := args.peek(); ok; _, ok = args.peek() {
-		like, err := buildOneQuery(args)
-		if err != nil {
-			return nil, err
-		}
-		likes = append(likes, like)
-	}
-
-	return likes.Any, nil
+	var result ledger.Like
+	var err error
+	func() {
+		defer func() {
+			if err := recover(); err != nil {
+				err = fmt.Errorf("panicked: %v", err)
+			}
+		}()
+		result, err = buildQuery(args)
+	}()
+	return result, err
 }
 
-func buildOneQuery(args args) (ledger.Like, error) {
-	word, ok := args.peek()
-	if !ok {
-		return nil, io.EOF
+func buildQuery(args args) (ledger.Like, error) {
+	likeName := func(s string) ledger.Like {
+		return ledger.LikeName(s)
+	}
+	andLike := func(a, b ledger.Like) ledger.Like {
+		return (ledger.Likes{a, b}).All
+	}
+	orLike := func(a, b ledger.Like) ledger.Like {
+		return (ledger.Likes{a, b}).Any
+	}
+	notLike := func(a ledger.Like) ledger.Like {
+		return ledger.LikeNot(a)
 	}
 
-	likes := make(ledger.Likes, 0)
+	if !args.more() {
+		return likeName(""), nil
+	}
+	like := likeName("ajskfdlsjfkdasj")
 
-	for _, ok := args.peek(); ok; _, ok = args.peek() {
-		switch word {
+	for args.more() {
+		switch args.peek() {
 		case "and":
-			if len(likes) == 0 {
-				return nil, fmt.Errorf("and without predicate")
-			}
 			args.pop()
-			like, err := buildOneQuery(args)
-			if err != nil {
-				return nil, err
+			var like ledger.Like
+			switch args.peek() {
+			case "not":
+				args.pop()
+				log.Println("and not", args.peek())
+				like = notLike(likeName(args.pop()))
+			default:
+				log.Println("and ", args.peek())
+				like = likeName(args.pop())
 			}
-			likes = append(likes, like)
+			like = andLike(like, like)
 		case "not":
 			args.pop()
-			like, err := buildOneQuery(args)
-			if err != nil {
-				return nil, err
-			}
-			likes = append(likes, like)
+			log.Println("or not ", args.peek())
+			like = orLike(like, notLike(
+				likeName(args.pop()),
+			))
 		default:
-			return nil, io.EOF
-			if next, _ := args.peek(); next != "and" {
-				return likes.All, nil
-			}
+			log.Println("or ", args.peek())
+			like = orLike(like,
+				likeName(args.pop()),
+			)
 		}
 	}
-	return nil, io.EOF
+
+	return like, nil
 }
 
 type args []string
 
 func (args *args) pop() string {
-	first := (*args)[0]
-	*args = (*args)[1:]
+	if !args.more() {
+		panic("expected more arguments")
+	}
+	first := ""
+	if len(*args) > 0 {
+		first = (*args)[0]
+		*args = (*args)[1:]
+	}
 	return first
 }
 
-func (args *args) peek() (string, bool) {
+func (args *args) peek() string {
 	if len(*args) == 0 {
-		return "", false
+		return ""
 	}
-	return (*args)[0], true
+	return (*args)[0]
+}
+
+func (args *args) more() bool {
+	return len(*args) > 0
 }