TRPL: deref coercions #24722
TRPL: deref coercions #24722
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| This is useful for writing custom pointer types. However, there’s a language | ||
| feature related to `Deref`: ‘deref coercions’. Here’s the rule: If you have a | ||
| type `U`, and it implements `Deref<Target=T>`, values of `&U` will | ||
| automatically convert to a `&T`. Here’s an example: |
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s/convert/coerce/
I think the distinction may matter in some places? I'm not super sure though
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Nice! Could this also mention somewhere that |
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r=me with those nits otherwise though! |
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Can we also mention (or link to) autoderef here somewhere? I'd like all of the deref magic to be mentioned in one place. |
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issues fixed, and @Manishearth 's section added 😄 |
| ```rust,ignore | ||
| f.foo(); | ||
| (*f).foo(); | ||
| (******f).foo(); |
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Did this mean to use & instead of *?
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well, i guess it actually meant to use & and * alternating, since that's the behavior, right?
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I think this means to say that a value of type &&&&&&&&&&&&&&&&Foo can still have methods defined on Foo called as the compiler will insert as many * operations as necessary (basically).
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adding to #24786 |
| ## Deref and method calls | ||
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| `Deref` will also kick in when calling a method. In other words, these are | ||
| the same two things in Rust: |
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Which 'two things' is this referring to?
r? @alexcrichton