The main [Tutorial - User Guide](../tutorial/index.md){.internal-link target=_blank} should be enough to give you a tour through all the main features of **FastAPI**.

In the next sections you will see other options, configurations, and additional features.

/// tip

The next sections are **not necessarily "advanced"**.

And it's possible that for your use case, the solution is in one of them.

///

pkg net, method (*Resolver) LookupSRV(context.Context, string, string, string) (string, []*SRV, error)
pkg net, method (*Resolver) LookupTXT(context.Context, string) ([]string, error)
pkg net, method (*UnixListener) SetUnlinkOnClose(bool)
pkg net, type Buffers [][]uint8
pkg net, type Dialer struct, Resolver *Resolver
pkg net, type Resolver struct
pkg net, type Resolver struct, PreferGo bool
pkg net/url, func PathEscape(string) string

      private final StrongKeyStrongValueEntry<K, V> next;

      LinkedStrongKeyStrongValueEntry(K key, int hash, StrongKeyStrongValueEntry<K, V> next) {
        super(key, hash);
        this.next = next;
      }

      @Override
      public StrongKeyStrongValueEntry<K, V> getNext() {
        return next;
      }
    }

    final Runnable runnable;
    final Executor executor;
    @Nullable RunnableExecutorPair next;

    RunnableExecutorPair(
        Runnable runnable, Executor executor, @Nullable RunnableExecutorPair next) {
      this.runnable = runnable;
      this.executor = executor;
      this.next = next;
    }
  }

    assertEquals(
        "next() should still return first element after peeking", "A", peekingIterator.next());

    assertEquals("Should be able to peek() at middle element", "B", peekingIterator.peek());
    assertEquals(
        "Should be able to peek() middle element multiple times", "B", peekingIterator.peek());
    assertEquals(

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Authenticator;
import java.net.HttpURLConnection;
import java.net.PasswordAuthentication;
import java.net.ProtocolException;
import java.net.URL;
import java.net.URLDecoder;
import java.security.Permission;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;

      int initialSize = map.size();
      boolean didRemove = entrySet.remove(entrySet.iterator().next());
      assertTrue(didRemove);
      assertEquals(initialSize - 1, map.size());
    } else {
      assertThrows(
          UnsupportedOperationException.class, () -> entrySet.remove(entrySet.iterator().next()));
    }
    assertInvariants(map);
  }

  public void testEntrySetRemoveMissingKey() {

        this.existPrePage = existPrePage;
    }

    /**
     * Checks if a next page exists.
     * @return true if a next page exists, false otherwise.
     */
    public boolean isExistNextPage() {
        return existNextPage;
    }

    /**
     * Sets whether a next page exists.
     * @param existNextPage true if a next page exists, false otherwise.
     */

        this.existPrePage = existPrePage;
    }

    /**
     * Checks if there is a next page.
     * @return true if next page exists, false otherwise
     */
    public boolean isExistNextPage() {
        return existNextPage;
    }

    /**
     * Sets whether a next page exists.
     * @param existNextPage true if next page exists
     */
    public void setExistNextPage(final boolean existNextPage) {

	return &Reader{r: r, curr: &regFileReader{r, 0}}
}

// Next advances to the next entry in the tar archive.
// The Header.Size determines how many bytes can be read for the next file.
// Any remaining data in the current file is automatically discarded.
// At the end of the archive, Next returns the error io.EOF.
//
// If Next encounters a non-local name (as defined by [filepath.IsLocal])