Crate hir_expand 

hir_expand deals with macro expansion.

Specifically, it implements a concept of MacroFile – a file whose syntax tree originates not from the text of some FileId, but from some macro expansion.

Re-exports

pub use crate::files::AstId;

pub use crate::files::ErasedAstId;

pub use crate::files::FileRange;

pub use crate::files::InFile;

pub use crate::files::InMacroFile;

pub use crate::files::InRealFile;

pub use intern;

pub use tt;

Modules

attrs

Defines the basics of attributes lowering.

builtin

Builtin macros and attributes

cfg_process 🔒

Processes out #[cfg] and #[cfg_attr] attributes from the input for the derive macro

change

Defines a unit of change that can applied to the database to get the next state. Changes are transactional.

declarative

Compiled declarative macro expanders (macro_rules! and macro)

eager

Eager expansion related utils

files

Things to wrap other things in file ids.

fixup 🔒

To make attribute macros work reliably when typing, we need to take care to fix up syntax errors in the code we’re passing to them.

hygiene

Machinery for hygienic macros.

inert_attr_macro

Builtin attributes resolved by nameres.

mod_path

A lowering for use-paths (more generally, paths without angle-bracketed segments).

name

See Name.

prettify_macro_expansion_ 🔒

Pretty printing of macros output.

proc_macro

Proc Macro Expander stuff

span_map

Span maps for real files and macro expansions.

Macros

__known_path

__path

__tool_path

impl_intern_lookup

quote

FIXME: It probably should implement in proc-macro

Structs

AttrMacroAttrIds

DeclarativeMacro

This struct contains AST for a single macro_rules definition. What might be very confusing is that AST has almost exactly the same shape as tt::TokenTree, but there’s a crucial difference: in macro rules, $ident and $()* have special meaning (see Var and Repeat data structures)

EagerCallInfo

EditionedFileId

ExpandError

ExpansionInfo

ExpansionInfo mainly describes how to map text range between src and expanded macro

MacroCallId

Macro ids. That’s probably the tricksiest bit in rust-analyzer, and the reason why we use salsa at all.

MacroCallLoc

MacroCallStyles

A set of MacroCallStyle values, allowing macros to indicate that they support more than one style.

MacroDefId

RenderedExpandError

ValueResult

Enums

AttrMacroAttrIdsRepr 🔒

ExpandErrorKind

ExpandTo

In Rust, macros expand token trees to token trees. When we want to turn a token tree into an AST node, we need to figure out what kind of AST node we want: something like foo can be a type, an expression, or a pattern.

HirFileId

MacroCallKind

MacroCallStyle

MacroDefKind

MacroKind

Constants

TOKEN_LIMIT 🔒

Total limit on the number of tokens produced by any macro invocation.

Traits

Intern

Lookup

Functions

check_tt_count 🔒

expand_unimplemented_builtin_macro 🔒

map_node_range_up

Maps up the text range out of the expansion hierarchy back into the original file its from.

map_node_range_up_rooted

Maps up the text range out of the expansion hierarchy back into the original file its from only considering the root spans contained. Unlike map_node_range_up, this will not return None if any anchors or syntax contexts differ.

prettify_macro_expansion

Inserts whitespace and replaces $crate in macro expansions.

proc_macro_span 🔒

Retrieves the span to be used for a proc-macro expansions spans. This is a firewall query as it requires parsing the file, which we don’t want proc-macros to directly depend on as that would cause to frequent invalidations, mainly because of the parse queries being LRU cached. If they weren’t the invalidations would only happen if the user wrote in the file that defines the proc-macro.

resolve_span

span_for_offset

Looks up the span at the given offset.

token_tree_to_syntax_node 🔒

Type Aliases

ExpandResult

MacroArgResult 🔒

This is just to ensure the types of MacroCallId::macro_arg_considering_derives and MacroCallId::macro_arg are the same.