Struct Span

pub struct Span { /* private fields */ }

A region of source code, along with macro expansion information.

Implementations

impl Span

pub fn call_site() -> Self

The span of the invocation of the current procedural macro.

Identifiers created with this span will be resolved as if they were written directly at the macro call location (call-site hygiene) and other code at the macro call site will be able to refer to them as well.

pub fn mixed_site() -> Self

The span located at the invocation of the procedural macro, but with local variables, labels, and $crate resolved at the definition site of the macro. This is the same hygiene behavior as macro_rules.

This function requires Rust 1.45 or later.

pub fn def_site() -> Self

A span that resolves at the macro definition site.

pub fn resolved_at(&self, other: Span) -> Span

Creates a new span with the same line/column information as self but that resolves symbols as though it were at other.

pub fn located_at(&self, other: Span) -> Span

Creates a new span with the same name resolution behavior as self but with the line/column information of other.

pub fn source_file(&self) -> SourceFile

The original source file into which this span points.

pub fn start(&self) -> LineColumn

Get the starting line/column in the source file for this span.

When executing in a procedural macro context, the returned line/column are only meaningful if compiled with a nightly toolchain. The stable toolchain does not have this information available. When executing outside of a procedural macro, such as main.rs or build.rs, the line/column are always meaningful regardless of toolchain.

pub fn end(&self) -> LineColumn

Get the ending line/column in the source file for this span.

When executing in a procedural macro context, the returned line/column are only meaningful if compiled with a nightly toolchain. The stable toolchain does not have this information available. When executing outside of a procedural macro, such as main.rs or build.rs, the line/column are always meaningful regardless of toolchain.

pub fn join(&self, other: Span) -> Option<Span>

Create a new span encompassing self and other.

Returns None if self and other are from different files.

Trait Implementations

impl Clone for Span

fn clone(&self) -> Span

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Span

Prints a span in a form convenient for debugging.

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for Span

fn eq(&self, other: &Span) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Span

impl Eq for Span

impl StructuralPartialEq for Span