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/**
 * A package to provide entry-point classes for the `Fluent` style.
 * 
 * The goal of the "fluent" style of the `pcond` library is to make it possible:
 * 
 * - To be able to rely on IDE's help for recalling what you can do now.
 * - To write tests in a readable and consistent manner.
 * - To show a readable report failure when a test fails.
 * - Not to need to a custom support class for your own class.
 * 
 * That is, if you have a following example code:
 * 
 * [source, java]
 * .Example Test Code
 * ----
 * public class FluentStyleExample {
 *   @Test
 *   public void givenKnownLastName_whenFindMembersByFullName_thenLastNastIsNotNullAndContainedInFullName() {
 *     // Find a user entry from a member database
 *     MemberDatabase database = new MemberDatabase();
 *     String lastName = database.lookUp("0001")
 *         .orElseThrow(NoSuchElementException::new)
 *         .lastName();
 *     List fullName = database.findMembersByLastName(lastName).get(0).toFullName();
 *     // Check if
 *     // - The last name of the entry is not null and not an empty string.
 *     // - The last name is "DOE".
 *     assertWhen(
 *         value(lastName)
 *             .then()
 *             .verifyWith(allOf(
 *                 isNotNull(),
 *                 not(isEmptyString()))),
 *         value(fullName).asListOfClass(String.class)
 *             .then()
 *             .contains("DOE"));
 *   }
 * }
 * ----
 * 
 * May result in the following output:
 * 
 * [%nowrap]
 * .Output Example
 * ----
 *  "Doe"               ->WHEN:treatAsIs      ->"Doe"                | "Doe"               ->WHEN:treatAsIs      ->"Doe"
 *                        THEN:&&             ->true                 |                       THEN:&&             ->true
 *                            isNotNull       ->true                 |                            isNotNull      ->true
 *                            !               ->true                 |                            !              ->true
 *                              isEmpty       ->false                |                              isEmpty      ->false
 *  ["John","Doe","PhD"]->WHEN:treatAsList    ->["John","Doe","PhD"] | ["John","Doe","PhD"]->WHEN:treatAsList    ->["John","Doe","PhD"]
 * X                      THEN:contains["DOE"]->true                 |                       THEN:contains["DOE"]->false
 * ----
 * 
 * == Special Types of `pcond`
 * 
 * In the `pcond` library divides an evaluation of an assertion into two stages.
 * "Transform" and "check".
 * Not like other assertion libraries, it has separated group of classes for each of them.
 * "Transformers"
 * 
 * In order to reduce the necessity of creating custom classes, it takes an approach, where
 * 
 * They are `String`, `Number`(`Integer`), `Boolean`, `List`, `Stream`, and (general) `Object`.
 * For each of them, special `Transformer` s and `Checker` s come with the `pcond` library to provide type specific methods, such as `containsString` for `String`.
 * 
 * 
 * 
 */
package com.github.dakusui.valid8j_pcond.fluent;