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Change use of "UFCS" to "fully-qualified function call syntax" #3366

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Change use of "UFCS" to "fully-qualified function call syntax" #3366

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15 changes: 11 additions & 4 deletions text/0132-ufcs.md
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Expand Up @@ -4,10 +4,14 @@

# Summary

This RFC describes a variety of extensions to allow any method to be
used as first-class functions. The same extensions also allow for
trait methods without receivers to be invoked in a more natural
fashion.
This RFC describes the fully-qualified syntax for making function calls,
which was previously called Unambiguous or Universal Function Call Syntax
(UFCS). The [Rust Reference section on call expressions] provides
an overview of this syntax, and reasons for the change in terminology.

There are a variety of extensions to allow any method to be used as
first-class functions. The same extensions also allow for trait methods
without receivers to be invoked in a more natural fashion.
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Changing the structure of this entire paragraph doesn't seem necessary to add the explanatory note, and usually RFCs are preserved as close to as-written as reasonable. The intent is good overall with this PR but please favor additive over subtractive changes.


First, at present, the notation `path::method()` can be used to invoke
inherent methods on types. For example, `Vec::new()` is used to create
Expand Down Expand Up @@ -210,3 +214,6 @@ to try and change the question:
type parameter. But there exists a lot of precedent for the current
approach and hence I think this is likely a bad idea (not to mention
that it's a drastic change).


[Rust Reference section on call expressions]: https://doc.rust-lang.org/reference/expressions/call-expr.html#disambiguating-function-calls
12 changes: 6 additions & 6 deletions text/0255-object-safety.md
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Expand Up @@ -70,11 +70,11 @@ where a trait object is used with a generic call and would be something like
"type error: SomeTrait does not implement SomeTrait" - no indication that the
non-object-safe method were to blame, only a failure in trait matching.

Another advantage of this proposal is that it implies that all
method-calls can always be rewritten into an equivalent [UFCS]
call. This simplifies the "core language" and makes method dispatch
notation -- which involves some non-trivial inference -- into a kind
of "sugar" for the more explicit UFCS notation.
Another advantage of this proposal is that it implies that all method-calls
can always be rewritten into an equivalent fully-qualified function call
(see [RFC 132]). This simplifies the "core language" and makes method dispatch
notation -- which involves some non-trivial inference -- into a kind of
"sugar" for the more explicit fully-qualified notation.
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This looks good, but is there a version that minimizes the diff?


# Detailed design

Expand Down Expand Up @@ -212,5 +212,5 @@ N/A
(2) specify that methods may include `where Self:Sized` to overcome
object safety restrictions.

[UFCS]: 0132-ufcs.md
[RFC 132]: 0132-ufcs.md
[RFC 546]: 0546-Self-not-sized-by-default.md