1#!/usr/bin/env python3
2#
3#   Copyright 2020 - The Android Open Source Project
4#
5#   Licensed under the Apache License, Version 2.0 (the "License");
6#   you may not use this file except in compliance with the License.
7#   You may obtain a copy of the License at
8#
9#       http://www.apache.org/licenses/LICENSE-2.0
10#
11#   Unless required by applicable law or agreed to in writing, software
12#   distributed under the License is distributed on an "AS IS" BASIS,
13#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14#   See the License for the specific language governing permissions and
15#   limitations under the License.
16
17
18class Capture(object):
19    """
20    Wrap a match function and use in its place, to capture the value
21    that matched. Specify an optional |capture_fn| to transform the
22    captured value.
23    """
24
25    def __init__(self, match_fn, capture_fn=None):
26        self._match_fn = match_fn
27        self._capture_fn = capture_fn
28        self._value = None
29
30    def __call__(self, obj):
31        if self._match_fn(obj) != True:
32            return False
33
34        if self._capture_fn is not None:
35            self._value = self._capture_fn(obj)
36        else:
37            self._value = obj
38        return True
39
40    def get(self):
41        return self._value
42