Rework user ops

Rework user ops in the following ways:
- User ops take either a const or path as an argument.
- The this value of the parent is carried through when a user op is
  invoked.

compiler/ast/ast.go

@@ -28,10 +28,6 @@ type Expr interface {
 	ExprAST()
 }
 
-type Param interface {
-	ParamAST()
-}
-
 type ID struct {
 	Kind string `json:"kind" unpack:""`
 	Name string `json:"name"`
@@ -216,10 +212,10 @@ type FuncDecl struct {
 }
 
 type OpDecl struct {
-	Kind   string  `json:"kind" unpack:""`
-	Name   string  `json:"name"`
-	Params []Param `json:"params"`
-	Body   Seq     `json:"body"`
+	Kind   string   `json:"kind" unpack:""`
+	Name   string   `json:"name"`
+	Params []string `json:"params"`
+	Body   Seq      `json:"body"`
 }
 
 func (*ConstDecl) DeclAST() {}
@@ -540,24 +536,3 @@ type Agg struct {
 	Expr  Expr   `json:"expr"`
 	Where Expr   `json:"where"`
 }
-
-// ----------------------------------------------------------------------------
-// Params
-
-type (
-	ConstParam struct {
-		Kind string `json:"kind" unpack:""`
-		Name string `json:"name"`
-	}
-	NamedParam struct {
-		Kind string `json:"kind" unpack:""`
-		Name string `json:"name"`
-	}
-	SpreadParam struct {
-		Kind string `json:"kind" unpack:""`
-	}
-)
-
-func (*ConstParam) ParamAST()  {}
-func (*NamedParam) ParamAST()  {}
-func (*SpreadParam) ParamAST() {}

compiler/ast/dag/expr.go

@@ -10,9 +10,6 @@ type (
 	VectorElem interface {
 		vectorElem()
 	}
-	Param interface {
-		paramDAG()
-	}
 )
 
 // Exprs
@@ -191,23 +188,3 @@ func TopLevelField(e Expr) (string, bool) {
 	}
 	return "", false
 }
-
-// Params
-
-type (
-	ConstParam struct {
-		Kind string `json:"kind" unpack:""`
-		Name string `json:"name"`
-	}
-	NamedParam struct {
-		Kind string `json:"kind" unpack:""`
-		Name string `json:"name"`
-	}
-	SpreadParam struct {
-		Kind string `json:"kind" unpack:""`
-	}
-)
-
-func (*ConstParam) paramDAG()  {}
-func (*NamedParam) paramDAG()  {}
-func (*SpreadParam) paramDAG() {}

compiler/ast/dag/op.go

@@ -145,17 +145,16 @@ type (
 		Cflag bool   `json:"cflag"`
 	}
 	UserOp struct {
-		Kind   string  `json:"kind" unpack:""`
-		Name   string  `json:"id"`
-		Params []Param `json:"params"`
-		Body   Seq     `json:"body"`
+		Kind   string   `json:"kind" unpack:""`
+		Name   string   `json:"id"`
+		Params []string `json:"params"`
+		Body   Seq      `json:"body"`
 	}
 	UserOpCall struct {
-		Kind   string     `json:"kind" unpack:""`
-		Name   string     `json:"name"`
-		Exprs  []Expr     `json:"exprs"`
-		Consts []*Literal `json:"consts"`
-		UserOp *UserOp    `json:"user_op"`
+		Kind  string `json:"kind" unpack:""`
+		Name  string `json:"name"`
+		Exprs []Expr `json:"exprs"`
+		Body  Seq    `json:"body"`
 	}
 	Yield struct {
 		Kind  string `json:"kind" unpack:""`

compiler/ast/dag/unpack.go

@@ -14,7 +14,6 @@ var unpacker = unpack.New(
 	Call{},
 	Combine{},
 	Conditional{},
-	ConstParam{},
 	Cut{},
 	Deleter{},
 	Dot{},
@@ -34,7 +33,6 @@ var unpacker = unpack.New(
 	Load{},
 	MapExpr{},
 	Merge{},
-	NamedParam{},
 	Over{},
 	OverExpr{},
 	Pass{},
@@ -53,7 +51,6 @@ var unpacker = unpack.New(
 	Slicer{},
 	Sort{},
 	Spread{},
-	SpreadParam{},
 	Summarize{},
 	Switch{},
 	Tail{},

compiler/ast/unpack.go

@@ -20,7 +20,6 @@ var unpacker = unpack.New(
 	astzed.CastValue{},
 	Conditional{},
 	ConstDecl{},
-	ConstParam{},
 	Cut{},
 	astzed.DefValue{},
 	Drop{},
@@ -41,7 +40,6 @@ var unpacker = unpack.New(
 	Join{},
 	Load{},
 	Merge{},
-	NamedParam{},
 	Over{},
 	Trunk{},
 	astzed.Map{},
@@ -91,7 +89,6 @@ var unpacker = unpack.New(
 	Where{},
 	Yield{},
 	Sample{},
-	SpreadParam{},
 )
 
 // UnmarshalOp transforms a JSON representation of an operator into an Op.

compiler/kernel/op.go

@@ -385,52 +385,16 @@ func (b *Builder) compileOver(parent zbuf.Puller, over *dag.Over) (zbuf.Puller,
 }
 
 func (b *Builder) compileUserOpCall(parent zbuf.Puller, u *dag.UserOpCall) (zbuf.Puller, error) {
-	// Construct the "this" record value.
-	var elems []expr.RecordElem
-	for i, p := range u.UserOp.Params {
-		if _, ok := p.(*dag.ConstParam); ok {
-			continue
-		}
-		val, err := compileExpr(u.Exprs[i])
-		if err != nil {
-			return nil, err
-		}
-		switch p := p.(type) {
-		case *dag.NamedParam:
-			elems = append(elems, expr.RecordElem{Name: p.Name, Field: val})
-		case *dag.SpreadParam:
-			elems = append(elems, expr.RecordElem{Spread: val})
-		default:
-			return nil, fmt.Errorf("internal error: unknown DAG param type: %#v", p)
-		}
-	}
-	this, err := expr.NewRecordExpr(b.octx.Zctx, elems)
-	if err != nil {
-		return nil, err
-	}
-	consts := make([]zed.Value, len(u.Consts))
-	for i, c := range u.Consts {
-		val, err := EvalAtCompileTime(b.octx.Zctx, c)
-		if err != nil {
-			return nil, err
-		}
-		consts[i] = *val
-	}
-	apply := op.NewApplier(b.octx, parent, this)
-	enter := op.NewEnterScope(apply, consts)
-	exits, err := b.compileSeq(u.UserOp.Body, []zbuf.Puller{enter})
+	exits, err := b.compileSeq(u.Body, []zbuf.Puller{parent})
 	if err != nil {
 		return nil, err
 	}
-	var exit zbuf.Puller
 	if len(exits) > 1 {
 		// This can happen when output of the body
 		// is a fork or switch.
-		exit = combine.New(b.octx, exits)
-	} else {
-		exit = exits[0]
+		return combine.New(b.octx, exits), nil
 	}
-	return op.NewExitScope(exit, len(consts)), nil
+	return exits[0], nil
 }
 
 func (b *Builder) compileAssignments(assignments []dag.Assignment) ([]expr.Assignment, error) {

compiler/optimizer/optimizer.go

@@ -87,7 +87,7 @@ func walk(seq dag.Seq, over bool, post func(dag.Seq) dag.Seq) dag.Seq {
 		case *dag.Scope:
 			op.Body = walk(op.Body, over, post)
 		case *dag.UserOpCall:
-			op.UserOp.Body = walk(op.UserOp.Body, over, post)
+			op.Body = walk(op.Body, over, post)
 		}
 	}
 	return post(seq)