81  * kind of a scope
87    * A map used to track whether identifiers without symbols are in the top-level scope.
102    * type of scope
118   export function isGlobalScope(scope: Scope): boolean {
119     return scope.kind === ScopeKind.GLOBAL;
122   export function isFunctionScope(scope: Scope): boolean {
123     return scope.kind === ScopeKind.FUNCTION;
126   export function isClassScope(scope: Scope): boolean {
127     return scope.kind === ScopeKind.CLASS;
130   export function isInterfaceScope(scope: Scope): boolean {
131     return scope.kind === ScopeKind.INTERFACE;
134   export function isEnumScope(scope: Scope): boolean {
135     return scope.kind === ScopeKind.ENUM;
138   export function isObjectLiteralScope(scope: Scope): boolean {
139     return scope.kind === ScopeKind.OBJECT_LITERAL;
143    * get a new scope.
144    * @param name - name of the scope.
145    * @param node - node of a current scope in ast.
146    * @param type - type of the scope.
147    * @param lexicalScope - indicates if the scope is a lexical scope.
148    * @param upper - parent scope of the current scope.
150   export class Scope {  class
151     // scope name
153     // kind of a scope, such as global ,function like, block ..
155     // node of a current scope in ast.
157     // parent scope of current scope
158     parent: Scope | undefined;
159     // sub scopes of current scope
160     children: Scope[];
162     // symbols define in current scope
165     // labels in current scope
176 …structor(name: string, node: Node, type: ScopeKind, lexicalScope: boolean = false, upper?: Scope) {
193      * add a sub scope to current scope
197     addChild(child: Scope): void {
202      * add definition symbol into current scope
214      * add label to current scope
256     scope: Scope;  property
259 …export function createLabel(node: LabeledStatement, scope: Scope, parent?: Label | undefined): Lab…
260     let labelName: string = '$' + scope.labels.length + '_' + node.label.text;
267       'scope': scope,
270     scope.labels.push(label);
284      * do scope analysis
292      * get root scope of a file
294     getRootScope(): Scope;
297      * find block Scope of a node
300     getScopeOfNode(node: Node): Scope | undefined;
305     let root: Scope;
306     let current: Scope;
307     let scopes: Scope[] = [];
332     function getRootScope(): Scope {
502         // add symbol of annotationDeclaration into global scope
517           // try to collect symbol for `A` in `import { A as B } from './file'; into current scope`
610       current = new Scope(scopeName, node, ScopeKind.OBJECT_LITERAL, false, current);
674       root = new Scope(scopeName, node, ScopeKind.GLOBAL, true);
679       // locals of a node(scope) is symbol that defines in current scope(node).
688       current = new Scope(scopeName, node, ScopeKind.CATCH, false, current);
719       current = new Scope(scopeName, node, ScopeKind.INTERFACE, true, current);
734        * if it is an anonymous scope, generate the scope name with a number,
735        * which is based on the order of its child scopes in the upper scope
738       current = new Scope(scopeName, node, ScopeKind.MODULE, true, current);
808         current = new Scope(scopeName, node, ScopeKind.FUNCTION, true, current);
835 …The `current` scope is the function's scope, the `current.parent` scope is where the function is d…
836           `foo` has already added in the parent scope, we need to add `bar` here too.
861       current = new Scope(scopeName, node, ScopeKind.SWITCH, false, current);
869 …* ES6+ class like scope, The members of a class aren't not allow to rename in rename identifiers t…
881         current = new Scope(scopeName, node, ScopeKind.CLASS, true, current);
899       current = new Scope(scopeName, node, ScopeKind.FOR, false, current);
909         // skip direct block scope in function scope
915       current = new Scope(scopeName, node, ScopeKind.BLOCK, false, current);
924       current = new Scope(scopeName, node, ScopeKind.INTERFACE, true, current);
944       current = new Scope(scopeName, node, ScopeKind.ENUM, true, current);
1033 …// labels within the same scope are allowed to be duplicated, so label names need to have numberin…
1039     function getScopeOfNode(node: Node): Scope | undefined {
1049       for (const scope of scopes) {  constant
1050         if (scope?.defs.has(sym)) {
1051           return scope;
1108     function tryAddExportNamesIntoParentScope(originalSymbol: Symbol, currentScope: Scope): void {
1112       let parentScope: Scope = currentScope.parent;
1119     function tryAddExportNamesIntoCurrentScope(originalSymbol: Symbol, currentScope: Scope): void {
1157   export function getNameWithScopeLoc(scope: Scope, name: string): string {
1158     return scope.loc + '#' + name;