43 lines
1.1 KiB
Rust
43 lines
1.1 KiB
Rust
use std::error::Error;
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use std::io;
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use std::process;
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fn run() -> Result<(), Box<dyn Error>> {
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let mut wtr = csv::Writer::from_writer(io::stdout());
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// We still need to write headers manually.
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wtr.write_record(&[
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"City",
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"State",
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"Population",
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"Latitude",
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"Longitude",
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])?;
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// But now we can write records by providing a normal Rust value.
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//
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// Note that the odd `None::<u64>` syntax is required because `None` on
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// its own doesn't have a concrete type, but Serde needs a concrete type
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// in order to serialize it. That is, `None` has type `Option<T>` but
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// `None::<u64>` has type `Option<u64>`.
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wtr.serialize((
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"Davidsons Landing",
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"AK",
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None::<u64>,
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65.2419444,
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-165.2716667,
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))?;
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wtr.serialize(("Kenai", "AK", Some(7610), 60.5544444, -151.2583333))?;
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wtr.serialize(("Oakman", "AL", None::<u64>, 33.7133333, -87.3886111))?;
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wtr.flush()?;
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Ok(())
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}
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fn main() {
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if let Err(err) = run() {
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println!("{}", err);
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process::exit(1);
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}
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}
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