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pkg/dev_compiler/tool/input_sdk/lib/core/pattern.dart

-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-part of dart.core;
-
-/**
- * An interface for basic searches within strings.
- */
-abstract class Pattern {
-  // NOTE: When using "start" index from the language library, call
-  // without an argument if start is zero. This allows backwards compatiblity
-  // with implementations of the older interface that didn't have the start
-  // index argument.
-  /**
-   * Match this pattern against the string repeatedly.
-   *
-   * If [start] is provided, matching will start at that index.
-   *
-   * The returned iterable lazily computes all the non-overlapping matches
-   * of the pattern on the string, ordered by start index.
-   * If a user only requests the first
-   * match, this function should not compute all possible matches.
-   *
-   * The matches are found by repeatedly finding the first match
-   * of the pattern on the string, starting from the end of the previous
-   * match, and initially starting from index zero.
-   *
-   * If the pattern matches the empty string at some point, the next
-   * match is found by starting at the previous match's end plus one.
-   */
-  Iterable<Match> allMatches(String string, [int start = 0]);
-
-  /**
-   * Match this pattern against the start of `string`.
-   *
-   * If [start] is provided, it must be an integer in the range `0` ..
-   * `string.length`. In that case, this patten is tested against the
-   * string at the [start] position. That is, a [Match] is returned if the
-   * pattern can match a part of the string starting from position [start].
-   * Returns `null` if the pattern doesn't match.
-   */
-  Match matchAsPrefix(String string, [int start = 0]);
-}
-
-/**
- * A result from searching within a string.
- *
- * A Match or an [Iterable] of Match objects is returned from [Pattern]
- * matching methods.
- *
- * The following example finds all matches of a [RegExp] in a [String]
- * and iterates through the returned iterable of Match objects.
- *
- *     RegExp exp = new RegExp(r"(\w+)");
- *     String str = "Parse my string";
- *     Iterable<Match> matches = exp.allMatches(str);
- *     for (Match m in matches) {
- *       String match = m.group(0);
- *       print(match);
- *     }
- *
- * The output of the example is:
- *
- *     Parse
- *     my
- *     string
- *
- * Some patterns, regular expressions in particular, may record subtrings
- * that were part of the matching. These are called _groups_ in the Match
- * object. Some patterns may never have any groups, and their matches always
- * have zero [groupCount].
- */
-abstract class Match {
-  /**
-   * Returns the index in the string where the match starts.
-   */
-  int get start;
-
-  /**
-   * Returns the index in the string after the last character of the
-   * match.
-   */
-  int get end;
-
-  /**
-   * Returns the string matched by the given [group].
-   *
-   * If [group] is 0, returns the match of the pattern.
-   *
-   * The result may be `null` if the pattern didn't assign a value to it
-   * as part of this match.
-   */
-  String group(int group);
-
-  /**
-   * Returns the string matched by the given [group].
-   *
-   * If [group] is 0, returns the match of the pattern.
-   *
-   * Short alias for [Match.group].
-   */
-  String operator [](int group);
-
-  /**
-   * Returns a list of the groups with the given indices.
-   *
-   * The list contains the strings returned by [group] for each index in
-   * [groupIndices].
-   */
-  List<String> groups(List<int> groupIndices);
-
-  /**
-   * Returns the number of captured groups in the match.
-   *
-   * Some patterns may capture parts of the input that was used to
-   * compute the full match. This is the number of captured groups,
-   * which is also the maximal allowed argument to the [group] method.
-   */
-  int get groupCount;
-
-  /**
-   * The string on which this match was computed.
-   */
-  String get input;
-
-  /**
-   * The pattern used to search in [input].
-   */
-  Pattern get pattern;
-}