Replace exists with explicit nil check (#10)

Author: jakebailey

internal/compiler/ast.go

@@ -1,7 +1,5 @@
 package compiler
 
-import "reflect"
-
 // Visitor
 
 type Visitor func(*Node) bool
@@ -22,12 +20,6 @@ func visitNodes(v Visitor, nodes []*Node) bool {
 	return false
 }
 
-// In situations where conversions from a pointer type may produce a typed nil, this function can be used
-// to check that the interface truly references an existing struct.
-func exists(i interface{}) bool {
-	return !(i == nil || reflect.ValueOf(i).IsNil())
-}
-
 // NodeFactory
 
 type NodeFactory struct {

internal/compiler/binder.go

@@ -572,7 +572,7 @@ func finishFlowLabel(label *FlowLabel) *FlowNode {
 }
 
 func (b *Binder) bind(node *Node) bool {
-	if !exists(node) {
+	if node == nil {
 		return false
 	}
 	node.parent = b.parent

internal/compiler/utilities.go

@@ -1000,7 +1000,7 @@ func isClassLike(node *Node) bool {
 }
 
 func declarationNameToString(name *Node) string {
-	if !exists(name) || name.Pos() == name.End() {
+	if name == nil || name.Pos() == name.End() {
 		return "(Missing)"
 	}
 	return getTextOfNode(name)