Method use

src/main/java/net/starlark/java/syntax/Resolver.java:826–875

(Identifier id)

  // Resolves a non-binding identifier to an existing binding, or null.
  @Nullable
  private Binding use(Identifier id) {
    String name = id.getName();

    // Locally defined in this function, comprehension,
    // or file block, or an enclosing one?
    Binding bind = lookupLexical(name, locals);
    if (bind != null) {
      return bind;
    }

    // Defined at toplevel (global, predeclared, universal)?
    bind = toplevel.get(name);
    if (bind != null) {
      return bind;
    }
    Scope scope;
    try {
      scope = module.resolve(name);
    } catch (Resolver.Module.Undefined ex) {
      if (!Identifier.isValid(name)) {
        // If Identifier was created by Parser.makeErrorExpression, it
        // contains misparsed text. Ignore ex and report an appropriate error.
        errorf(id, "contains syntax errors");
      } else if (ex.candidates != null) {
        // Exception provided toplevel candidates.
        // Show spelling suggestions of all symbols in scope,
        String suggestion = SpellChecker.didYouMean(name, getAllSymbols(ex.candidates));
        errorf(id, "%s%s", ex.getMessage(), suggestion);
      } else {
        errorf(id, "%s", ex.getMessage());
      }
      return null;
    }
    switch (scope) {
      case GLOBAL:
        bind = new Binding(scope, globals.size(), /* isSyntactic= */ false, id);
        // Accumulate globals in module.
        globals.add(name);
        break;
      case PREDECLARED:
      case UNIVERSAL:
        bind = new Binding(scope, 0, /* isSyntactic= */ false, id); // index not used
        break;
      default:
        throw new IllegalStateException("bad scope: " + scope);
    }
    toplevel.put(name, bind);
    return bind;
  }

  // lookupLexical finds a lexically enclosing local binding of the name,
  // plumbing it through enclosing functions as needed.