prune/
lib.rs

1#![feature(test)]
2// Copyright 2019 YechaoLi
3//
4// Licensed under the Apache License, Version 2.0 (the "License");
5// you may not use this file except in compliance with the License.
6// You may obtain a copy of the License at
7//
8//     http://www.apache.org/licenses/LICENSE-2.0
9//
10// Unless required by applicable law or agreed to in writing, software
11// distributed under the License is distributed on an "AS IS" BASIS,
12// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13// See the License for the specific language governing permissions and
14// limitations under the License.
15
16#[macro_use]
17extern crate lazy_static;
18
19pub mod trim;
20
21pub trait Prune: IsNone {
22    fn prune(self) -> Self;
23}
24
25pub trait IsNone {
26    fn is_none(&self) -> bool {
27        false
28    }
29}
30
31impl<T> IsNone for Option<T> {
32    fn is_none(&self) -> bool {
33        self.is_none()
34    }
35}
36
37impl<T> Prune for Option<T>
38where
39    T: Prune + IsNone,
40{
41    fn prune(self) -> Self {
42        match self {
43            None => None,
44            Some(s) => {
45                let s = s.prune();
46                if s.is_none() {
47                    None
48                } else {
49                    Some(s)
50                }
51            }
52        }
53    }
54}
55
56impl<T> IsNone for Vec<T> {}
57
58impl<T> Prune for Vec<T>
59where
60    T: Prune,
61{
62    fn prune(self) -> Self {
63        self.into_iter().map(Prune::prune).collect()
64    }
65}
66
67#[derive(Debug)]
68pub enum Operator {
69    Trim,
70    TrimStart,
71    TrimEnd,
72    NoWhitespace,
73    Nested,
74    Custom(String),
75}
76
77macro_rules! tuple_impls {
78    ($(
79        ($(($idx:tt)),+)
80    )+) => {
81        tuple_impls! {
82            $(
83                ($((T, $idx)),+)
84            )+
85        }
86    };
87    ($(
88        ($(($T:ident, $idx:tt)),+)
89    )+) => {
90        $(
91            impl<T> IsNone for ($($T),+) {}
92
93            impl<T> Prune for ($($T),+) where T: Prune {
94                fn prune(self) -> Self {
95                    (
96                        $(self.$idx.prune()),+
97                    )
98                }
99            }
100        )+
101    };
102}
103
104tuple_impls! {
105    ((0), (1))
106    ((0), (1), (2))
107    ((0), (1), (2), (3))
108    ((0), (1), (2), (3), (4))
109    ((0), (1), (2), (3), (4), (5))
110    ((0), (1), (2), (3), (4), (5), (6))
111    ((0), (1), (2), (3), (4), (5), (6), (7))
112    ((0), (1), (2), (3), (4), (5), (6), (7), (8))
113    ((0), (1), (2), (3), (4), (5), (6), (7), (8), (9))
114    ((0), (1), (2), (3), (4), (5), (6), (7), (8), (9), (10))
115    ((0), (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11))
116    ((0), (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11), (12))
117}
prune/lib.rs

prune/
lib.rs
