Extended range operator

pkg/compiler/compiler_test.go

@@ -1553,6 +1553,36 @@ func TestRangeOperator(t *testing.T) {
 
 		So(string(out), ShouldEqual, `[2,4,6,8,10,12,14,16,18,20]`)
 	})
+
+	Convey("Should use variables", t, func() {
+		out := compiler.New().MustCompile(`
+				LET max = 10
+				
+				FOR i IN 1..max
+					RETURN i * 2
+		`).MustRun(context.Background())
+
+		So(string(out), ShouldEqual, `[2,4,6,8,10,12,14,16,18,20]`)
+
+		out2 := compiler.New().MustCompile(`
+				LET min = 1
+				
+				FOR i IN min..10
+					RETURN i * 2
+		`).MustRun(context.Background())
+
+		So(string(out2), ShouldEqual, `[2,4,6,8,10,12,14,16,18,20]`)
+
+		out3 := compiler.New().MustCompile(`
+				LET min = 1
+				LET max = 10
+				
+				FOR i IN min..max
+					RETURN i * 2
+		`).MustRun(context.Background())
+
+		So(string(out3), ShouldEqual, `[2,4,6,8,10,12,14,16,18,20]`)
+	})
 }
 
 func TestInOperator(t *testing.T) {

pkg/compiler/visitor.go

@@ -664,20 +664,19 @@ func (v *visitor) doVisitVariableDeclaration(ctx *fql.VariableDeclarationContext
 }
 
 func (v *visitor) doVisitRangeOperator(ctx *fql.RangeOperatorContext, scope *scope) (collections.IterableExpression, error) {
-	ints := ctx.AllIntegerLiteral()
-
-	left, err := v.doVisitIntegerLiteral(ints[0].(*fql.IntegerLiteralContext))
+	exp, err := v.doVisitChildren(ctx, scope)
 
 	if err != nil {
 		return nil, err
 	}
 
-	right, err := v.doVisitIntegerLiteral(ints[1].(*fql.IntegerLiteralContext))
-
-	if err != nil {
-		return nil, err
+	if len(exp) < 2 {
+		return nil, errors.Wrap(ErrInvalidToken, ctx.GetText())
 	}
 
+	left := exp[0]
+	right := exp[1]
+
 	return operators.NewRangeOperator(
 		v.getSourceMap(ctx),
 		left,

pkg/parser/antlr/FqlParser.g4

@@ -133,7 +133,7 @@ variable
     ;
 
 rangeOperator
-    : integerLiteral Range integerLiteral
+    : (integerLiteral | variable) Range (integerLiteral | variable)
     ;
 
 arrayLiteral