package once

// Singleton contains a pointer to T that must be set once.
// Until the value is set all Get() calls will block.
type Singleton[T any] struct {
	v   *T
	set chan struct{}
}

// NewSingleton creates a new unset singleton.
func NewSingleton[T any]() *Singleton[T] {
	return &Singleton[T]{set: make(chan struct{}), v: nil}
}

// Get will return the singleton value.
func (s *Singleton[T]) Get() *T {
	<-s.set
	return s.v

{* ../../docs_src/security/tutorial007_an_py310.py hl[1,12:24] *}

This would be similar to:

```Python
if not (credentials.username == "stanleyjobson") or not (credentials.password == "swordfish"):
    # Return some error
    ...
```

But by using the `secrets.compare_digest()` it will be secure against a type of attacks called "timing attacks".

### Timing Attacks { #timing-attacks }

   * first permutation will be in ascending order, and the last will be in descending order.
   *
   * <p>Elements that compare equal are considered equal and no new permutations are created by
   * swapping them.
   *
   * <p>An empty iterable has only one permutation, which is an empty list.
   *
   * @param elements the original iterable whose elements have to be permuted.

body:
  - type: textarea
    id: feature
    attributes:
      label: What would you like to be added?
      description: |
        Feature requests are unlikely to make progress as issues. Please consider engaging with SIGs on slack and mailing lists, instead.
        A proposal that works through the design along with the implications of the change can be opened as a KEP.
        See https://git.k8s.io/enhancements/keps#kubernetes-enhancement-proposals-keps

# `Request` class

You can declare a parameter in a *path operation function* or dependency to be of type `Request` and then you can access the raw request object directly, without any validation, etc.

Read more about it in the [FastAPI docs about using Request directly](https://fastapi.tiangolo.com/advanced/using-request-directly/)

You can import it directly from `fastapi`:

```python
from fastapi import Request
```

/// tip

    /**
     * Stores a document in the search index with the specified parameters and data.
     *
     * @param paramMap the data store parameters containing configuration and metadata
     * @param dataMap the document data to be indexed as key-value pairs
     */
    void store(DataStoreParams paramMap, Map<String, Object> dataMap);

    /**
     * Returns the total number of documents processed by this callback.
     *

 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *

        SuggestIndexer indexer = suggester.indexer();
        // Setting null index name should be allowed (though may cause issues later)
        indexer.setIndexName(null);
    }

    @Test
    public void test_setNullSupportedFields() throws Exception {
        SuggestIndexer indexer = suggester.indexer();
        // Setting null fields should be allowed
        indexer.setSupportedFields(null);
    }

    @Test

	}
	return string(s) == text, nil
}

// matcher - Finds `pat` in `text`, and returns the part remainder of
// `text`, after the match. If leadingPercent is false, `pat` must be
// the prefix of `text`, otherwise it must be a substring.
func matcher(text, pat string, leadingPercent bool) (res string, match bool) {
	if !leadingPercent {
		res = strings.TrimPrefix(text, pat)
		if len(text) == len(res) {

import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * Denotes that a bean should be created as a singleton instance.
 * <p>
 * Singleton-scoped beans are instantiated once and reused throughout the entire
 * Maven execution. This scope should be used for stateless services or components
 * that can be safely shared across the entire build process.
 * <p>
 * Example usage:
 * <pre>
 * {@literal @}Singleton