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34 lines
782 B
34 lines
782 B
3 years ago
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# 代码风格
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## 使用[tap](https://github.com/myrrlyn/tap)库来实现`point-free`编程风格
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```rust
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use tap::{Tap, TapFallible};
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type SomeValue = String;
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type SomeOtherValue = String;
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type SomeError = String;
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fn foo() -> Result<SomeValue, SomeError> {
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Ok("foo".into())
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}
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fn bar(input: &str) -> Result<SomeOtherValue, SomeError> {
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if input == "bar" {
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Ok("Success".into())
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} else {
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Err("This is a failure message".into())
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}
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}
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fn my_fun() -> Result<SomeOtherValue, SomeError> {
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foo()
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.tap_err(|err| println!("foo() failed with error: {}", err))
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.and_then(|foo_val| bar(&foo_val))
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.tap(|res| println!("bar() returned result: {:?}", res))
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}
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fn main() {
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let result = my_fun();
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println!("{:?}", result);
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}
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```
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