fix type-to-string conv. + fix binary type check + add modulo + rework import (now include)

core/nodes.go

@@ -43,6 +43,7 @@ const (
 	AccessNodeType
 	AliasNodeType
 	IndexNodeType
+	IncludeNodeType
 	BreakpointNodeType
 )
 
@@ -294,6 +295,7 @@ const (
 	BinarySubtraction
 	BinaryMultiplication
 	BinaryDivision
+	BinaryModulo
 
 	BinaryBooleanAnd
 	BinaryBooleanOr
@@ -317,6 +319,8 @@ func (n BinaryOperation) Symbol() string {
 		return "*"
 	case BinaryDivision:
 		return "/"
+	case BinaryModulo:
+		return "%"
 	case BinaryEquality:
 		return "=="
 	case BinaryInequality:
@@ -690,6 +694,25 @@ func (n AliasNode) Bounds() (Pos, Pos) {
 	return n.start, n.end
 }
 
+type IncludeNode struct {
+	path *StringNode
+
+	start Pos
+	end   Pos
+}
+
+func (n IncludeNode) Type() NodeType {
+	return IncludeNodeType
+}
+
+func (n IncludeNode) String() string {
+	return fmt.Sprintf("include \"%s\"", n.path)
+}
+
+func (n IncludeNode) Bounds() (Pos, Pos) {
+	return n.start, n.end
+}
+
 type IndexNode struct {
 	source Node
 	index  Node