2 // ignore-cloudabi no std::fs
5 use std::io::{Read, self};
6 use std::num::ParseIntError;
9 fn on_method() -> Result<i32, ParseIntError> {
10 Ok("1".parse::<i32>()? + "2".parse::<i32>()?)
13 fn in_chain() -> Result<String, ParseIntError> {
14 Ok("3".parse::<i32>()?.to_string())
17 fn on_call() -> Result<i32, ParseIntError> {
18 fn parse<T: FromStr>(s: &str) -> Result<T, T::Err> {
25 fn nested() -> Result<i32, ParseIntError> {
26 Ok("5".parse::<i32>()?.to_string().parse()?)
29 fn on_path() -> Result<i32, ParseIntError> {
30 let x = "6".parse::<i32>();
35 fn on_macro() -> Result<i32, ParseIntError> {
40 Ok(id!("7".parse::<i32>())?)
43 fn on_parens() -> Result<i32, ParseIntError> {
44 let x = "8".parse::<i32>();
49 fn on_block() -> Result<i32, ParseIntError> {
50 let x = "9".parse::<i32>();
55 fn on_field() -> Result<i32, ParseIntError> {
56 struct Pair<A, B> { a: A, b: B }
58 let x = Pair { a: "10".parse::<i32>(), b: 0 };
63 fn on_tuple_field() -> Result<i32, ParseIntError> {
64 let x = ("11".parse::<i32>(), 0);
69 fn on_try() -> Result<i32, ParseIntError> {
70 let x = "12".parse::<i32>().map(|i| i.to_string().parse::<i32>());
75 fn on_binary_op() -> Result<i32, ParseIntError> {
76 let x = 13 - "14".parse::<i32>()?;
77 let y = "15".parse::<i32>()? - 16;
78 let z = "17".parse::<i32>()? - "18".parse::<i32>()?;
83 fn on_index() -> Result<i32, ParseIntError> {
85 let y = "0".parse::<usize>();
90 fn on_args() -> Result<i32, ParseIntError> {
91 fn sub(x: i32, y: i32) -> i32 { x - y }
99 fn on_if() -> Result<i32, ParseIntError> {
107 fn on_if_let() -> Result<i32, ParseIntError> {
108 Ok(if let Ok(..) = "24".parse::<i32>() {
115 fn on_match() -> Result<i32, ParseIntError> {
116 Ok(match "27".parse::<i32>() {
117 Err(..) => "28".parse::<i32>(),
118 Ok(..) => "29".parse::<i32>(),
122 fn tight_binding() -> Result<bool, ()> {
123 fn ok<T>(x: T) -> Result<T, ()> { Ok(x) }
130 fn merge_error() -> Result<i32, Error> {
131 let mut s = String::new();
133 File::open("foo.txt")?.read_to_string(&mut s)?;
135 Ok(s.parse::<i32>()? + 1)
139 assert_eq!(Ok(3), on_method());
141 assert_eq!(Ok("3".to_string()), in_chain());
143 assert_eq!(Ok(4), on_call());
145 assert_eq!(Ok(5), nested());
147 assert_eq!(Ok(6), on_path());
149 assert_eq!(Ok(7), on_macro());
151 assert_eq!(Ok(8), on_parens());
153 assert_eq!(Ok(9), on_block());
155 assert_eq!(Ok(10), on_field());
157 assert_eq!(Ok(11), on_tuple_field());
159 assert_eq!(Ok(12), on_try());
161 assert_eq!(Ok(-3), on_binary_op());
163 assert_eq!(Ok(19), on_index());
165 assert_eq!(Ok(-1), on_args());
167 assert_eq!(Ok(22), on_if());
169 assert_eq!(Ok(25), on_if_let());
171 assert_eq!(Ok(29), on_match());
173 assert_eq!(Ok(false), tight_binding());
178 Parse(ParseIntError),
181 impl From<io::Error> for Error {
182 fn from(e: io::Error) -> Error {
187 impl From<ParseIntError> for Error {
188 fn from(e: ParseIntError) -> Error {