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36 lines
1.1 KiB
Rust
36 lines
1.1 KiB
Rust
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#![allow(unused_must_use)]
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#![warn(write_literal)]
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use std::io::Write;
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fn main() {
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let mut v = Vec::new();
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// These should be fine
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write!(&mut v, "Hello");
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writeln!(&mut v, "Hello");
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let world = "world";
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writeln!(&mut v, "Hello {}", world);
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writeln!(&mut v, "3 in hex is {:X}", 3);
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// These should throw warnings
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write!(&mut v, "Hello {}", "world");
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writeln!(&mut v, "Hello {} {}", world, "world");
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writeln!(&mut v, "Hello {}", "world");
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writeln!(&mut v, "10 / 4 is {}", 2.5);
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writeln!(&mut v, "2 + 1 = {}", 3);
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writeln!(&mut v, "2 + 1 = {:.4}", 3);
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writeln!(&mut v, "2 + 1 = {:5.4}", 3);
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writeln!(&mut v, "Debug test {:?}", "hello, world");
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// positional args don't change the fact
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// that we're using a literal -- this should
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// throw a warning
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writeln!(&mut v, "{0} {1}", "hello", "world");
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writeln!(&mut v, "{1} {0}", "hello", "world");
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// named args shouldn't change anything either
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writeln!(&mut v, "{foo} {bar}", foo = "hello", bar = "world");
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writeln!(&mut v, "{bar} {foo}", foo = "hello", bar = "world");
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}
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