pub struct SpannedValue<T> { /* private fields */ }
Expand description

A value and an associated position in source code. The main use case for this is to preserve position information to emit warnings from proc macros. You can use a SpannedValue<T> as a field in any struct that implements or derives any of darling’s core traits.

To access the underlying value, use the struct’s Deref implementation.

Defaulting

This type is meant to be used in conjunction with attribute-extracted options, but the user may not always explicitly set those options in their source code. In this case, using Default::default() will create an instance which points to Span::call_site().

Implementations

Get the source code location referenced by this struct.

Trait Implementations

Converts this type into a shared reference of the (usually inferred) input type.

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

Returns the “default value” for a type. Read more

The resulting type after dereferencing.

Dereferences the value.

Mutably dereferences the value.

Converts to this type from the input type.

Create an instance from syn::DeriveInput, or return an error.

Create an instance from a syn::Meta by dispatching to the format-appropriate trait function. This generally should not be overridden by implementers. Read more

Create an instance from the presence of the word in the attribute with no additional options specified. Read more

Create an instance from a list of nested meta items.

Create an instance from a literal value of either foo = "bar" or foo("bar"). This dispatches to the appropriate method based on the type of literal encountered, and generally should not be overridden by implementers. Read more

Create an instance from a char literal in a value position.

Create an instance from a string literal in a value position.

Create an instance from a bool literal in a value position.

Create an instance from syn::Variant, or return an error.

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

🔬 This is a nightly-only experimental API. (toowned_clone_into)

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.