1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
|
use std::convert::From;
use std::collections::HashMap;
/// A configuration value.
///
/// Has an underlying or native type that comes from the configuration source
/// but will be coerced into the requested type.
#[derive(Debug, Clone, PartialEq)]
pub enum Value {
Nil,
String(String),
Integer(i64),
Float(f64),
Boolean(bool),
Table(HashMap<String, Value>),
Array(Vec<Value>),
}
impl Value {
/// Converts `self` into a string, if possible.
/// Returns None otherwise.
pub fn into_str(self) -> Option<String> {
match self {
Value::String(value) => Some(value),
Value::Integer(value) => Some(value.to_string()),
Value::Float(value) => Some(value.to_string()),
Value::Boolean(value) => Some(value.to_string()),
_ => None,
}
}
/// Converts `self` into a bool, if possible.
/// Returns None otherwise.
pub fn into_bool(self) -> Option<bool> {
match self {
Value::Boolean(value) => Some(value),
Value::Integer(value) => Some(value != 0),
Value::Float(value) => Some(value != 0.0),
Value::String(ref value) => {
match value.to_lowercase().as_ref() {
"1" | "true" | "on" | "yes" => Some(true),
"0" | "false" | "off" | "no" => Some(false),
_ => None,
}
}
_ => None,
}
}
/// Converts `self` into an i64, if possible.
/// Returns None otherwise.
pub fn into_int(self) -> Option<i64> {
match self {
Value::Integer(value) => Some(value),
Value::String(ref value) => value.parse().ok(),
Value::Boolean(value) => Some(if value { 1 } else { 0 }),
Value::Float(value) => Some(value.round() as i64),
_ => None,
}
}
/// Converts `self` into a f64, if possible.
/// Returns None otherwise.
pub fn into_float(self) -> Option<f64> {
match self {
Value::Float(value) => Some(value),
Value::String(ref value) => value.parse().ok(),
Value::Integer(value) => Some(value as f64),
Value::Boolean(value) => Some(if value { 1.0 } else { 0.0 }),
_ => None,
}
}
/// If the `Value` is a Table, returns the associated Map.
/// Returns None otherwise.
pub fn into_table(self) -> Option<HashMap<String, Value>> {
match self {
Value::Table(value) => Some(value),
_ => None,
}
}
/// If the `Value` is an Array, returns the associated Vector.
/// Returns None otherwise.
pub fn into_array(self) -> Option<Vec<Value>> {
match self {
Value::Array(value) => Some(value),
_ => None,
}
}
}
// Generalized construction from type into variant is needed
// for setting configuration values
impl From<String> for Value {
fn from(value: String) -> Value {
Value::String(value.into())
}
}
impl<'a> From<&'a str> for Value {
fn from(value: &'a str) -> Value {
Value::String(value.into())
}
}
impl From<i64> for Value {
fn from(value: i64) -> Value {
Value::Integer(value)
}
}
impl From<f64> for Value {
fn from(value: f64) -> Value {
Value::Float(value)
}
}
impl From<bool> for Value {
fn from(value: bool) -> Value {
Value::Boolean(value)
}
}
impl<T> From<HashMap<String, T>> for Value
where T: Into<Value>
{
fn from(values: HashMap<String, T>) -> Value {
let mut r = HashMap::new();
for (k, v) in values {
r.insert(k.clone(), v.into());
}
Value::Table(r)
}
}
impl<T> From<Vec<T>> for Value
where T: Into<Value>
{
fn from(values: Vec<T>) -> Value {
let mut l = Vec::new();
for v in values {
l.push(v.into());
}
Value::Array(l)
}
}
|
