<img src="/img/tutorial/dependencies/image01.png">

## Simple usage { #simple-usage }

If you look at it, *path operation functions* are declared to be used whenever a *path* and *operation* matches, and then **FastAPI** takes care of calling the function with the correct parameters, extracting the data from the request.

Actually, all (or most) of the web frameworks work in this same way.

Otherwise, the path for `/users/{user_id}` would match also for `/users/me`, "thinking" that it's receiving a parameter `user_id` with a value of `"me"`.

Similarly, you cannot redefine a path operation:

{* ../../docs_src/path_params/tutorial003b.py hl[6,11] *}

The first one will always be used since the path matches first.

## Predefined values { #predefined-values }

     * @return true if enumeration is done, false otherwise
     */
    protected abstract boolean isDone();

    /**
     * Fetches more entries from the server.
     *
     * @return true if more entries were fetched, false otherwise
     * @throws CIFSException if an error occurs during fetching
     */
    protected abstract boolean fetchMore() throws CIFSException;

    /**
     * Gets the current batch of results.

import assertk.assertThat
import assertk.assertions.isEqualTo
import assertk.assertions.isLessThan
import assertk.assertions.isLessThanOrEqualTo
import assertk.assertions.isSameInstanceAs
import assertk.assertions.matches
import java.net.UnknownHostException
import mockwebserver3.MockResponse
import mockwebserver3.MockWebServer
import mockwebserver3.junit5.StartStop
import okhttp3.HttpUrl
import okhttp3.Interceptor

   */
  public static Throwable getRootCause(Throwable throwable) {
    // Keep a second pointer that slowly walks the causal chain. If the fast pointer ever catches
    // the slower pointer, then there's a loop.
    Throwable slowPointer = throwable;
    boolean advanceSlowPointer = false;

    Throwable cause;
    while ((cause = throwable.getCause()) != null) {

			} else {
				// has size in data type and not equal
				// Since the following code is frequently called in the for loop, reg optimization is needed here
				matches2 := regFullDataType.FindAllStringSubmatch(fullDataType, -1)
				if !field.PrimaryKey &&
					(len(matches2) == 1 && matches2[0][1] != fmt.Sprint(length) && ok) {
					alterColumn = true
				}
			}
		}
	}

	// check precision

    //                                                                        Small Helper
    //                                                                        ============
    /**
     * Verifies that the CRUD mode matches the expected mode.
     *
     * @param crudMode the actual CRUD mode
     * @param expectedMode the expected CRUD mode
     */
    protected void verifyCrudMode(final int crudMode, final int expectedMode) {

    //                                                                        Small Helper
    //                                                                        ============
    /**
     * Verifies that the CRUD mode matches the expected mode.
     *
     * @param crudMode the actual CRUD mode
     * @param expectedMode the expected CRUD mode
     */
    protected void verifyCrudMode(final int crudMode, final int expectedMode) {

        String result = crawlJob.execute();

        assertNotNull(crawlJob.sessionId);
        // Check format: yyyyMMddHHmmss
        assertEquals(14, crawlJob.sessionId.length());
        assertTrue(crawlJob.sessionId.matches("\\d{14}"));
        assertTrue(result.contains("Session Id: " + crawlJob.sessionId));
    }

    // Test with negative max crawler processes
    public void test_execute_negativeMaxProcesses() {

                && queue.removeLastOccurrence(submittedTask);
        // If the delegate is directExecutor(), the submitted runnable could have thrown a REE. But
        // that's handled by the log check that catches RuntimeExceptions in the queue worker.
        if (!(t instanceof RejectedExecutionException) || removed) {
          throw t;
        }
      }
      return;
    }

    /*