//
// Copyright 2019 Stijn de Witt. Some rights reserved.
// Licensed under the MIT Open Source license. 
// https://opensource.org/licenses/MIT
// See LICENSE for details.
//
// Based on code copyright 2018 Google Inc. All Rights Reserved.
// Licensed under the Apache License, Version 2.0.
// http://www.apache.org/licenses/LICENSE-2.0
// See LICENSE-MDC for details.
// 
// Unless required by applicable law or agreed to in writing, software
// distributed under these licenses is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the licenses for the specific language governing permissions and
// limitations under these licenses.
// 

// This variable is not intended to be overridden externally; it uses !default to avoid being reset
// every time this file is imported.
$mdc-base-styles-emitted_: () !default;

@mixin mdc-base-emit-once($key) {
  @if not index($mdc-base-styles-emitted_, $key) {
    $mdc-base-styles-emitted_: append($mdc-base-styles-emitted_, $key, comma) !global;

    @content;
  }
}