diff --git a/src/librustc_error_codes/error_codes/E0062.md b/src/librustc_error_codes/error_codes/E0062.md index 0ebeb1bd78e..64fc027b885 100644 --- a/src/librustc_error_codes/error_codes/E0062.md +++ b/src/librustc_error_codes/error_codes/E0062.md @@ -1,6 +1,6 @@ -This error indicates that during an attempt to build a struct or struct-like -enum variant, one of the fields was specified more than once. Erroneous code -example: +A struct's or struct-like enum variant's field was specified more than once. + +Erroneous code example: ```compile_fail,E0062 struct Foo { @@ -15,7 +15,9 @@ fn main() { } ``` -Each field should be specified exactly one time. Example: +This error indicates that during an attempt to build a struct or struct-like +enum variant, one of the fields was specified more than once. Each field should +be specified exactly one time. Example: ``` struct Foo { diff --git a/src/librustc_error_codes/error_codes/E0063.md b/src/librustc_error_codes/error_codes/E0063.md index 0d1f60437ac..0e611deac42 100644 --- a/src/librustc_error_codes/error_codes/E0063.md +++ b/src/librustc_error_codes/error_codes/E0063.md @@ -1,5 +1,6 @@ -This error indicates that during an attempt to build a struct or struct-like -enum variant, one of the fields was not provided. Erroneous code example: +A struct's or struct-like enum variant's field was not provided. + +Erroneous code example: ```compile_fail,E0063 struct Foo { diff --git a/src/librustc_error_codes/error_codes/E0067.md b/src/librustc_error_codes/error_codes/E0067.md index 101b96f7983..11041bb53ee 100644 --- a/src/librustc_error_codes/error_codes/E0067.md +++ b/src/librustc_error_codes/error_codes/E0067.md @@ -1,33 +1,15 @@ -The left-hand side of a compound assignment expression must be a place -expression. A place expression represents a memory location and includes -item paths (ie, namespaced variables), dereferences, indexing expressions, -and field references. +An invalid left-hand side expression was used on an assignment operation. -Let's start with some erroneous code examples: +Erroneous code example: ```compile_fail,E0067 -use std::collections::LinkedList; - -// Bad: assignment to non-place expression -LinkedList::new() += 1; - -// ... - -fn some_func(i: &mut i32) { - i += 12; // Error : '+=' operation cannot be applied on a reference ! -} +12 += 1; // error! ``` -And now some working examples: +You need to have a place expression to be able to assign it something. For +example: ``` -let mut i : i32 = 0; - -i += 12; // Good ! - -// ... - -fn some_func(i: &mut i32) { - *i += 12; // Good ! -} +let mut x: i8 = 12; +x += 1; // ok! ``` diff --git a/src/librustc_error_codes/error_codes/E0069.md b/src/librustc_error_codes/error_codes/E0069.md index ad3b1803b54..7367a5c0922 100644 --- a/src/librustc_error_codes/error_codes/E0069.md +++ b/src/librustc_error_codes/error_codes/E0069.md @@ -1,5 +1,7 @@ The compiler found a function whose body contains a `return;` statement but -whose return type is not `()`. An example of this is: +whose return type is not `()`. + +Erroneous code example: ```compile_fail,E0069 // error diff --git a/src/librustc_error_codes/error_codes/E0070.md b/src/librustc_error_codes/error_codes/E0070.md index 1a56080a097..97522af3da8 100644 --- a/src/librustc_error_codes/error_codes/E0070.md +++ b/src/librustc_error_codes/error_codes/E0070.md @@ -1,3 +1,26 @@ +An assignment operator was used on a non-place expression. + +Erroneous code examples: + +```compile_fail,E0070 +struct SomeStruct { + x: i32, + y: i32, +} + +const SOME_CONST: i32 = 12; + +fn some_other_func() {} + +fn some_function() { + SOME_CONST = 14; // error: a constant value cannot be changed! + 1 = 3; // error: 1 isn't a valid place! + some_other_func() = 4; // error: we cannot assign value to a function! + SomeStruct::x = 12; // error: SomeStruct a structure name but it is used + // like a variable! +} +``` + The left-hand side of an assignment operator must be a place expression. A place expression represents a memory location and can be a variable (with optional namespacing), a dereference, an indexing expression or a field @@ -7,35 +30,14 @@ More details can be found in the [Expressions] section of the Reference. [Expressions]: https://doc.rust-lang.org/reference/expressions.html#places-rvalues-and-temporaries -Now, we can go further. Here are some erroneous code examples: - -```compile_fail,E0070 -struct SomeStruct { - x: i32, - y: i32 -} - -const SOME_CONST : i32 = 12; - -fn some_other_func() {} - -fn some_function() { - SOME_CONST = 14; // error : a constant value cannot be changed! - 1 = 3; // error : 1 isn't a valid place! - some_other_func() = 4; // error : we cannot assign value to a function! - SomeStruct.x = 12; // error : SomeStruct a structure name but it is used - // like a variable! -} -``` - And now let's give working examples: ``` struct SomeStruct { x: i32, - y: i32 + y: i32, } -let mut s = SomeStruct {x: 0, y: 0}; +let mut s = SomeStruct { x: 0, y: 0 }; s.x = 3; // that's good !