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-rw-r--r--vendor/quick-error/examples/context.rs43
1 files changed, 43 insertions, 0 deletions
diff --git a/vendor/quick-error/examples/context.rs b/vendor/quick-error/examples/context.rs
new file mode 100644
index 000000000..1d406613e
--- /dev/null
+++ b/vendor/quick-error/examples/context.rs
@@ -0,0 +1,43 @@
+use quick_error::{quick_error, ResultExt};
+use std::env;
+use std::fs::File;
+use std::io::{self, stderr, Read, Write};
+use std::num::ParseIntError;
+use std::path::{Path, PathBuf};
+
+quick_error! {
+ #[derive(Debug)]
+ pub enum Error {
+ NoFileName {}
+ Io(err: io::Error, path: PathBuf) {
+ display("could not read file {:?}: {}", path, err)
+ context(path: &'a Path, err: io::Error)
+ -> (err, path.to_path_buf())
+ }
+ Parse(err: ParseIntError, path: PathBuf) {
+ display("could not parse file {:?}: {}", path, err)
+ context(path: &'a Path, err: ParseIntError)
+ -> (err, path.to_path_buf())
+ }
+ }
+}
+
+fn parse_file() -> Result<u64, Error> {
+ let fname = env::args().skip(1).next().ok_or(Error::NoFileName)?;
+ let fname = Path::new(&fname);
+ let mut file = File::open(fname).context(fname)?;
+ let mut buf = String::new();
+ file.read_to_string(&mut buf).context(fname)?;
+ Ok(buf.parse().context(fname)?)
+}
+
+fn main() {
+ match parse_file() {
+ Ok(val) => {
+ println!("Read: {}", val);
+ }
+ Err(e) => {
+ writeln!(&mut stderr(), "Error: {}", e).ok();
+ }
+ }
+}