flow like the river

BACK_BACK/node_modules/graphql/language/predicates.d.ts

@@ -0,0 +1,36 @@
+import {
+  ASTNode,
+  DefinitionNode,
+  ExecutableDefinitionNode,
+  SelectionNode,
+  ValueNode,
+  TypeNode,
+  TypeSystemDefinitionNode,
+  TypeDefinitionNode,
+  TypeSystemExtensionNode,
+  TypeExtensionNode,
+} from './ast';
+
+export function isDefinitionNode(node: ASTNode): node is DefinitionNode;
+
+export function isExecutableDefinitionNode(
+  node: ASTNode,
+): node is ExecutableDefinitionNode;
+
+export function isSelectionNode(node: ASTNode): node is SelectionNode;
+
+export function isValueNode(node: ASTNode): node is ValueNode;
+
+export function isTypeNode(node: ASTNode): node is TypeNode;
+
+export function isTypeSystemDefinitionNode(
+  node: ASTNode,
+): node is TypeSystemDefinitionNode;
+
+export function isTypeDefinitionNode(node: ASTNode): node is TypeDefinitionNode;
+
+export function isTypeSystemExtensionNode(
+  node: ASTNode,
+): node is TypeSystemExtensionNode;
+
+export function isTypeExtensionNode(node: ASTNode): node is TypeExtensionNode;