Enum rustc_ast_passes::ast_validation::ForbiddenLetReason

source · 
pub(crate) enum ForbiddenLetReason {
    GenericForbidden,
    NotSupportedOr(Span),
    NotSupportedParentheses(Span),
}
Expand description

Used to forbid let expressions in certain syntactic locations.

Variants

GenericForbidden

let is not valid and the source environment is not important

NotSupportedOr(Span)

A let chain with the || operator

NotSupportedParentheses(Span)

A let chain with invalid parentheses

For example, let 1 = 1 && (expr && expr) is allowed but (let 1 = 1 && (let 1 = 1 && (let 1 = 1))) && let a = 1 is not

Trait Implementations

Add a subdiagnostic to an existing diagnostic.
Returns a copy of the value. Read more
Performs copy-assignment from source. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference’s “Type Layout” chapter for details on type layout guarantees.

Size: 12 bytes

Size for each variant:

  • GenericForbidden: 0 bytes
  • NotSupportedOr: 8 bytes
  • NotSupportedParentheses: 8 bytes