1 //! A support library for macro authors when defining new macros.
3 //! This library, provided by the standard distribution, provides the types
4 //! consumed in the interfaces of procedurally defined macro definitions such as
5 //! function-like macros `#[proc_macro]`, macro attributes `#[proc_macro_attribute]` and
6 //! custom derive attributes`#[proc_macro_derive]`.
8 //! See [the book] for more.
10 //! [the book]: ../book/ch19-06-macros.html#procedural-macros-for-generating-code-from-attributes
12 #![stable(feature = "proc_macro_lib", since = "1.15.0")]
13 #![deny(missing_docs)]
15 html_playground_url = "https://play.rust-lang.org/",
16 issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/",
17 test(no_crate_inject, attr(deny(warnings))),
18 test(attr(allow(dead_code, deprecated, unused_variables, unused_mut)))
20 // This library is copied into rust-analyzer to allow loading rustc compiled proc macros.
21 // Please avoid unstable features where possible to minimize the amount of changes necessary
22 // to make it compile with rust-analyzer on stable.
23 #![feature(rustc_allow_const_fn_unstable)]
24 #![feature(staged_api)]
25 #![feature(allow_internal_unstable)]
26 #![feature(decl_macro)]
27 #![feature(negative_impls)]
28 #![feature(restricted_std)]
29 #![feature(rustc_attrs)]
30 #![feature(min_specialization)]
31 #![recursion_limit = "256"]
33 #[unstable(feature = "proc_macro_internals", issue = "27812")]
39 #[unstable(feature = "proc_macro_diagnostic", issue = "54140")]
40 pub use diagnostic::{Diagnostic, Level, MultiSpan};
42 use std::cmp::Ordering;
43 use std::ops::RangeBounds;
44 use std::path::PathBuf;
45 use std::str::FromStr;
46 use std::{error, fmt, iter, mem};
48 /// Determines whether proc_macro has been made accessible to the currently
51 /// The proc_macro crate is only intended for use inside the implementation of
52 /// procedural macros. All the functions in this crate panic if invoked from
53 /// outside of a procedural macro, such as from a build script or unit test or
54 /// ordinary Rust binary.
56 /// With consideration for Rust libraries that are designed to support both
57 /// macro and non-macro use cases, `proc_macro::is_available()` provides a
58 /// non-panicking way to detect whether the infrastructure required to use the
59 /// API of proc_macro is presently available. Returns true if invoked from
60 /// inside of a procedural macro, false if invoked from any other binary.
61 #[stable(feature = "proc_macro_is_available", since = "1.57.0")]
62 pub fn is_available() -> bool {
63 bridge::Bridge::is_available()
66 /// The main type provided by this crate, representing an abstract stream of
67 /// tokens, or, more specifically, a sequence of token trees.
68 /// The type provide interfaces for iterating over those token trees and, conversely,
69 /// collecting a number of token trees into one stream.
71 /// This is both the input and output of `#[proc_macro]`, `#[proc_macro_attribute]`
72 /// and `#[proc_macro_derive]` definitions.
73 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
75 pub struct TokenStream(bridge::client::TokenStream);
77 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
78 impl !Send for TokenStream {}
79 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
80 impl !Sync for TokenStream {}
82 /// Error returned from `TokenStream::from_str`.
83 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
88 #[stable(feature = "proc_macro_lexerror_impls", since = "1.44.0")]
89 impl fmt::Display for LexError {
90 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
91 f.write_str("cannot parse string into token stream")
95 #[stable(feature = "proc_macro_lexerror_impls", since = "1.44.0")]
96 impl error::Error for LexError {}
98 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
99 impl !Send for LexError {}
100 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
101 impl !Sync for LexError {}
103 /// Error returned from `TokenStream::expand_expr`.
104 #[unstable(feature = "proc_macro_expand", issue = "90765")]
107 pub struct ExpandError;
109 #[unstable(feature = "proc_macro_expand", issue = "90765")]
110 impl fmt::Display for ExpandError {
111 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
112 f.write_str("macro expansion failed")
116 #[unstable(feature = "proc_macro_expand", issue = "90765")]
117 impl error::Error for ExpandError {}
119 #[unstable(feature = "proc_macro_expand", issue = "90765")]
120 impl !Send for ExpandError {}
122 #[unstable(feature = "proc_macro_expand", issue = "90765")]
123 impl !Sync for ExpandError {}
126 /// Returns an empty `TokenStream` containing no token trees.
127 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
128 pub fn new() -> TokenStream {
129 TokenStream(bridge::client::TokenStream::new())
132 /// Checks if this `TokenStream` is empty.
133 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
134 pub fn is_empty(&self) -> bool {
138 /// Parses this `TokenStream` as an expression and attempts to expand any
139 /// macros within it. Returns the expanded `TokenStream`.
141 /// Currently only expressions expanding to literals will succeed, although
142 /// this may be relaxed in the future.
144 /// NOTE: In error conditions, `expand_expr` may leave macros unexpanded,
145 /// report an error, failing compilation, and/or return an `Err(..)`. The
146 /// specific behavior for any error condition, and what conditions are
147 /// considered errors, is unspecified and may change in the future.
148 #[unstable(feature = "proc_macro_expand", issue = "90765")]
149 pub fn expand_expr(&self) -> Result<TokenStream, ExpandError> {
150 match bridge::client::TokenStream::expand_expr(&self.0) {
151 Ok(stream) => Ok(TokenStream(stream)),
152 Err(_) => Err(ExpandError),
157 /// Attempts to break the string into tokens and parse those tokens into a token stream.
158 /// May fail for a number of reasons, for example, if the string contains unbalanced delimiters
159 /// or characters not existing in the language.
160 /// All tokens in the parsed stream get `Span::call_site()` spans.
162 /// NOTE: some errors may cause panics instead of returning `LexError`. We reserve the right to
163 /// change these errors into `LexError`s later.
164 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
165 impl FromStr for TokenStream {
168 fn from_str(src: &str) -> Result<TokenStream, LexError> {
169 Ok(TokenStream(bridge::client::TokenStream::from_str(src)))
173 // N.B., the bridge only provides `to_string`, implement `fmt::Display`
174 // based on it (the reverse of the usual relationship between the two).
175 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
176 impl ToString for TokenStream {
177 fn to_string(&self) -> String {
182 /// Prints the token stream as a string that is supposed to be losslessly convertible back
183 /// into the same token stream (modulo spans), except for possibly `TokenTree::Group`s
184 /// with `Delimiter::None` delimiters and negative numeric literals.
185 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
186 impl fmt::Display for TokenStream {
187 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
188 f.write_str(&self.to_string())
192 /// Prints token in a form convenient for debugging.
193 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
194 impl fmt::Debug for TokenStream {
195 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
196 f.write_str("TokenStream ")?;
197 f.debug_list().entries(self.clone()).finish()
201 #[stable(feature = "proc_macro_token_stream_default", since = "1.45.0")]
202 impl Default for TokenStream {
203 fn default() -> Self {
208 #[unstable(feature = "proc_macro_quote", issue = "54722")]
209 pub use quote::{quote, quote_span};
211 /// Creates a token stream containing a single token tree.
212 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
213 impl From<TokenTree> for TokenStream {
214 fn from(tree: TokenTree) -> TokenStream {
215 TokenStream(bridge::client::TokenStream::from_token_tree(match tree {
216 TokenTree::Group(tt) => bridge::TokenTree::Group(tt.0),
217 TokenTree::Punct(tt) => bridge::TokenTree::Punct(tt.0),
218 TokenTree::Ident(tt) => bridge::TokenTree::Ident(tt.0),
219 TokenTree::Literal(tt) => bridge::TokenTree::Literal(tt.0),
224 /// Collects a number of token trees into a single stream.
225 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
226 impl iter::FromIterator<TokenTree> for TokenStream {
227 fn from_iter<I: IntoIterator<Item = TokenTree>>(trees: I) -> Self {
228 trees.into_iter().map(TokenStream::from).collect()
232 /// A "flattening" operation on token streams, collects token trees
233 /// from multiple token streams into a single stream.
234 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
235 impl iter::FromIterator<TokenStream> for TokenStream {
236 fn from_iter<I: IntoIterator<Item = TokenStream>>(streams: I) -> Self {
237 let mut builder = bridge::client::TokenStreamBuilder::new();
238 streams.into_iter().for_each(|stream| builder.push(stream.0));
239 TokenStream(builder.build())
243 #[stable(feature = "token_stream_extend", since = "1.30.0")]
244 impl Extend<TokenTree> for TokenStream {
245 fn extend<I: IntoIterator<Item = TokenTree>>(&mut self, trees: I) {
246 self.extend(trees.into_iter().map(TokenStream::from));
250 #[stable(feature = "token_stream_extend", since = "1.30.0")]
251 impl Extend<TokenStream> for TokenStream {
252 fn extend<I: IntoIterator<Item = TokenStream>>(&mut self, streams: I) {
253 // FIXME(eddyb) Use an optimized implementation if/when possible.
254 *self = iter::once(mem::replace(self, Self::new())).chain(streams).collect();
258 /// Public implementation details for the `TokenStream` type, such as iterators.
259 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
260 pub mod token_stream {
261 use crate::{bridge, Group, Ident, Literal, Punct, TokenStream, TokenTree};
263 /// An iterator over `TokenStream`'s `TokenTree`s.
264 /// The iteration is "shallow", e.g., the iterator doesn't recurse into delimited groups,
265 /// and returns whole groups as token trees.
267 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
268 pub struct IntoIter(bridge::client::TokenStreamIter);
270 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
271 impl Iterator for IntoIter {
272 type Item = TokenTree;
274 fn next(&mut self) -> Option<TokenTree> {
275 self.0.next().map(|tree| match tree {
276 bridge::TokenTree::Group(tt) => TokenTree::Group(Group(tt)),
277 bridge::TokenTree::Punct(tt) => TokenTree::Punct(Punct(tt)),
278 bridge::TokenTree::Ident(tt) => TokenTree::Ident(Ident(tt)),
279 bridge::TokenTree::Literal(tt) => TokenTree::Literal(Literal(tt)),
284 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
285 impl IntoIterator for TokenStream {
286 type Item = TokenTree;
287 type IntoIter = IntoIter;
289 fn into_iter(self) -> IntoIter {
290 IntoIter(self.0.into_iter())
295 /// `quote!(..)` accepts arbitrary tokens and expands into a `TokenStream` describing the input.
296 /// For example, `quote!(a + b)` will produce an expression, that, when evaluated, constructs
297 /// the `TokenStream` `[Ident("a"), Punct('+', Alone), Ident("b")]`.
299 /// Unquoting is done with `$`, and works by taking the single next ident as the unquoted term.
300 /// To quote `$` itself, use `$$`.
301 #[unstable(feature = "proc_macro_quote", issue = "54722")]
302 #[allow_internal_unstable(proc_macro_def_site, proc_macro_internals)]
303 #[rustc_builtin_macro]
304 pub macro quote($($t:tt)*) {
305 /* compiler built-in */
308 #[unstable(feature = "proc_macro_internals", issue = "27812")]
312 /// A region of source code, along with macro expansion information.
313 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
314 #[derive(Copy, Clone)]
315 pub struct Span(bridge::client::Span);
317 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
318 impl !Send for Span {}
319 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
320 impl !Sync for Span {}
322 macro_rules! diagnostic_method {
323 ($name:ident, $level:expr) => {
324 /// Creates a new `Diagnostic` with the given `message` at the span
326 #[unstable(feature = "proc_macro_diagnostic", issue = "54140")]
327 pub fn $name<T: Into<String>>(self, message: T) -> Diagnostic {
328 Diagnostic::spanned(self, $level, message)
334 /// A span that resolves at the macro definition site.
335 #[unstable(feature = "proc_macro_def_site", issue = "54724")]
336 pub fn def_site() -> Span {
337 Span(bridge::client::Span::def_site())
340 /// The span of the invocation of the current procedural macro.
341 /// Identifiers created with this span will be resolved as if they were written
342 /// directly at the macro call location (call-site hygiene) and other code
343 /// at the macro call site will be able to refer to them as well.
344 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
345 pub fn call_site() -> Span {
346 Span(bridge::client::Span::call_site())
349 /// A span that represents `macro_rules` hygiene, and sometimes resolves at the macro
350 /// definition site (local variables, labels, `$crate`) and sometimes at the macro
351 /// call site (everything else).
352 /// The span location is taken from the call-site.
353 #[stable(feature = "proc_macro_mixed_site", since = "1.45.0")]
354 pub fn mixed_site() -> Span {
355 Span(bridge::client::Span::mixed_site())
358 /// The original source file into which this span points.
359 #[unstable(feature = "proc_macro_span", issue = "54725")]
360 pub fn source_file(&self) -> SourceFile {
361 SourceFile(self.0.source_file())
364 /// The `Span` for the tokens in the previous macro expansion from which
365 /// `self` was generated from, if any.
366 #[unstable(feature = "proc_macro_span", issue = "54725")]
367 pub fn parent(&self) -> Option<Span> {
368 self.0.parent().map(Span)
371 /// The span for the origin source code that `self` was generated from. If
372 /// this `Span` wasn't generated from other macro expansions then the return
373 /// value is the same as `*self`.
374 #[unstable(feature = "proc_macro_span", issue = "54725")]
375 pub fn source(&self) -> Span {
376 Span(self.0.source())
379 /// Gets the starting line/column in the source file for this span.
380 #[unstable(feature = "proc_macro_span", issue = "54725")]
381 pub fn start(&self) -> LineColumn {
382 self.0.start().add_1_to_column()
385 /// Gets the ending line/column in the source file for this span.
386 #[unstable(feature = "proc_macro_span", issue = "54725")]
387 pub fn end(&self) -> LineColumn {
388 self.0.end().add_1_to_column()
391 /// Creates an empty span pointing to directly before this span.
392 #[unstable(feature = "proc_macro_span_shrink", issue = "87552")]
393 pub fn before(&self) -> Span {
394 Span(self.0.before())
397 /// Creates an empty span pointing to directly after this span.
398 #[unstable(feature = "proc_macro_span_shrink", issue = "87552")]
399 pub fn after(&self) -> Span {
403 /// Creates a new span encompassing `self` and `other`.
405 /// Returns `None` if `self` and `other` are from different files.
406 #[unstable(feature = "proc_macro_span", issue = "54725")]
407 pub fn join(&self, other: Span) -> Option<Span> {
408 self.0.join(other.0).map(Span)
411 /// Creates a new span with the same line/column information as `self` but
412 /// that resolves symbols as though it were at `other`.
413 #[stable(feature = "proc_macro_span_resolved_at", since = "1.45.0")]
414 pub fn resolved_at(&self, other: Span) -> Span {
415 Span(self.0.resolved_at(other.0))
418 /// Creates a new span with the same name resolution behavior as `self` but
419 /// with the line/column information of `other`.
420 #[stable(feature = "proc_macro_span_located_at", since = "1.45.0")]
421 pub fn located_at(&self, other: Span) -> Span {
422 other.resolved_at(*self)
425 /// Compares to spans to see if they're equal.
426 #[unstable(feature = "proc_macro_span", issue = "54725")]
427 pub fn eq(&self, other: &Span) -> bool {
431 /// Returns the source text behind a span. This preserves the original source
432 /// code, including spaces and comments. It only returns a result if the span
433 /// corresponds to real source code.
435 /// Note: The observable result of a macro should only rely on the tokens and
436 /// not on this source text. The result of this function is a best effort to
437 /// be used for diagnostics only.
438 #[unstable(feature = "proc_macro_span", issue = "54725")]
439 pub fn source_text(&self) -> Option<String> {
443 // Used by the implementation of `Span::quote`
445 #[unstable(feature = "proc_macro_internals", issue = "27812")]
446 pub fn save_span(&self) -> usize {
450 // Used by the implementation of `Span::quote`
452 #[unstable(feature = "proc_macro_internals", issue = "27812")]
453 pub fn recover_proc_macro_span(id: usize) -> Span {
454 Span(bridge::client::Span::recover_proc_macro_span(id))
457 diagnostic_method!(error, Level::Error);
458 diagnostic_method!(warning, Level::Warning);
459 diagnostic_method!(note, Level::Note);
460 diagnostic_method!(help, Level::Help);
463 /// Prints a span in a form convenient for debugging.
464 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
465 impl fmt::Debug for Span {
466 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
471 /// A line-column pair representing the start or end of a `Span`.
472 #[unstable(feature = "proc_macro_span", issue = "54725")]
473 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
474 pub struct LineColumn {
475 /// The 1-indexed line in the source file on which the span starts or ends (inclusive).
476 #[unstable(feature = "proc_macro_span", issue = "54725")]
478 /// The 1-indexed column (number of bytes in UTF-8 encoding) in the source
479 /// file on which the span starts or ends (inclusive).
480 #[unstable(feature = "proc_macro_span", issue = "54725")]
485 fn add_1_to_column(self) -> Self {
486 LineColumn { line: self.line, column: self.column + 1 }
490 #[unstable(feature = "proc_macro_span", issue = "54725")]
491 impl !Send for LineColumn {}
492 #[unstable(feature = "proc_macro_span", issue = "54725")]
493 impl !Sync for LineColumn {}
495 #[unstable(feature = "proc_macro_span", issue = "54725")]
496 impl Ord for LineColumn {
497 fn cmp(&self, other: &Self) -> Ordering {
498 self.line.cmp(&other.line).then(self.column.cmp(&other.column))
502 #[unstable(feature = "proc_macro_span", issue = "54725")]
503 impl PartialOrd for LineColumn {
504 fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
505 Some(self.cmp(other))
509 /// The source file of a given `Span`.
510 #[unstable(feature = "proc_macro_span", issue = "54725")]
512 pub struct SourceFile(bridge::client::SourceFile);
515 /// Gets the path to this source file.
518 /// If the code span associated with this `SourceFile` was generated by an external macro, this
519 /// macro, this might not be an actual path on the filesystem. Use [`is_real`] to check.
521 /// Also note that even if `is_real` returns `true`, if `--remap-path-prefix` was passed on
522 /// the command line, the path as given might not actually be valid.
524 /// [`is_real`]: Self::is_real
525 #[unstable(feature = "proc_macro_span", issue = "54725")]
526 pub fn path(&self) -> PathBuf {
527 PathBuf::from(self.0.path())
530 /// Returns `true` if this source file is a real source file, and not generated by an external
531 /// macro's expansion.
532 #[unstable(feature = "proc_macro_span", issue = "54725")]
533 pub fn is_real(&self) -> bool {
534 // This is a hack until intercrate spans are implemented and we can have real source files
535 // for spans generated in external macros.
536 // https://github.com/rust-lang/rust/pull/43604#issuecomment-333334368
541 #[unstable(feature = "proc_macro_span", issue = "54725")]
542 impl fmt::Debug for SourceFile {
543 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
544 f.debug_struct("SourceFile")
545 .field("path", &self.path())
546 .field("is_real", &self.is_real())
551 #[unstable(feature = "proc_macro_span", issue = "54725")]
552 impl PartialEq for SourceFile {
553 fn eq(&self, other: &Self) -> bool {
558 #[unstable(feature = "proc_macro_span", issue = "54725")]
559 impl Eq for SourceFile {}
561 /// A single token or a delimited sequence of token trees (e.g., `[1, (), ..]`).
562 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
565 /// A token stream surrounded by bracket delimiters.
566 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
567 Group(#[stable(feature = "proc_macro_lib2", since = "1.29.0")] Group),
569 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
570 Ident(#[stable(feature = "proc_macro_lib2", since = "1.29.0")] Ident),
571 /// A single punctuation character (`+`, `,`, `$`, etc.).
572 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
573 Punct(#[stable(feature = "proc_macro_lib2", since = "1.29.0")] Punct),
574 /// A literal character (`'a'`), string (`"hello"`), number (`2.3`), etc.
575 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
576 Literal(#[stable(feature = "proc_macro_lib2", since = "1.29.0")] Literal),
579 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
580 impl !Send for TokenTree {}
581 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
582 impl !Sync for TokenTree {}
585 /// Returns the span of this tree, delegating to the `span` method of
586 /// the contained token or a delimited stream.
587 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
588 pub fn span(&self) -> Span {
590 TokenTree::Group(ref t) => t.span(),
591 TokenTree::Ident(ref t) => t.span(),
592 TokenTree::Punct(ref t) => t.span(),
593 TokenTree::Literal(ref t) => t.span(),
597 /// Configures the span for *only this token*.
599 /// Note that if this token is a `Group` then this method will not configure
600 /// the span of each of the internal tokens, this will simply delegate to
601 /// the `set_span` method of each variant.
602 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
603 pub fn set_span(&mut self, span: Span) {
605 TokenTree::Group(ref mut t) => t.set_span(span),
606 TokenTree::Ident(ref mut t) => t.set_span(span),
607 TokenTree::Punct(ref mut t) => t.set_span(span),
608 TokenTree::Literal(ref mut t) => t.set_span(span),
613 /// Prints token tree in a form convenient for debugging.
614 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
615 impl fmt::Debug for TokenTree {
616 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
617 // Each of these has the name in the struct type in the derived debug,
618 // so don't bother with an extra layer of indirection
620 TokenTree::Group(ref tt) => tt.fmt(f),
621 TokenTree::Ident(ref tt) => tt.fmt(f),
622 TokenTree::Punct(ref tt) => tt.fmt(f),
623 TokenTree::Literal(ref tt) => tt.fmt(f),
628 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
629 impl From<Group> for TokenTree {
630 fn from(g: Group) -> TokenTree {
635 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
636 impl From<Ident> for TokenTree {
637 fn from(g: Ident) -> TokenTree {
642 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
643 impl From<Punct> for TokenTree {
644 fn from(g: Punct) -> TokenTree {
649 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
650 impl From<Literal> for TokenTree {
651 fn from(g: Literal) -> TokenTree {
652 TokenTree::Literal(g)
656 // N.B., the bridge only provides `to_string`, implement `fmt::Display`
657 // based on it (the reverse of the usual relationship between the two).
658 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
659 impl ToString for TokenTree {
660 fn to_string(&self) -> String {
662 TokenTree::Group(ref t) => t.to_string(),
663 TokenTree::Ident(ref t) => t.to_string(),
664 TokenTree::Punct(ref t) => t.to_string(),
665 TokenTree::Literal(ref t) => t.to_string(),
670 /// Prints the token tree as a string that is supposed to be losslessly convertible back
671 /// into the same token tree (modulo spans), except for possibly `TokenTree::Group`s
672 /// with `Delimiter::None` delimiters and negative numeric literals.
673 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
674 impl fmt::Display for TokenTree {
675 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
676 f.write_str(&self.to_string())
680 /// A delimited token stream.
682 /// A `Group` internally contains a `TokenStream` which is surrounded by `Delimiter`s.
684 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
685 pub struct Group(bridge::client::Group);
687 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
688 impl !Send for Group {}
689 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
690 impl !Sync for Group {}
692 /// Describes how a sequence of token trees is delimited.
693 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
694 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
697 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
700 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
703 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
706 /// An invisible delimiter, that may, for example, appear around tokens coming from a
707 /// "macro variable" `$var`. It is important to preserve operator priorities in cases like
708 /// `$var * 3` where `$var` is `1 + 2`.
709 /// Invisible delimiters might not survive roundtrip of a token stream through a string.
710 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
715 /// Creates a new `Group` with the given delimiter and token stream.
717 /// This constructor will set the span for this group to
718 /// `Span::call_site()`. To change the span you can use the `set_span`
720 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
721 pub fn new(delimiter: Delimiter, stream: TokenStream) -> Group {
722 Group(bridge::client::Group::new(delimiter, stream.0))
725 /// Returns the delimiter of this `Group`
726 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
727 pub fn delimiter(&self) -> Delimiter {
731 /// Returns the `TokenStream` of tokens that are delimited in this `Group`.
733 /// Note that the returned token stream does not include the delimiter
735 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
736 pub fn stream(&self) -> TokenStream {
737 TokenStream(self.0.stream())
740 /// Returns the span for the delimiters of this token stream, spanning the
744 /// pub fn span(&self) -> Span {
747 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
748 pub fn span(&self) -> Span {
752 /// Returns the span pointing to the opening delimiter of this group.
755 /// pub fn span_open(&self) -> Span {
758 #[stable(feature = "proc_macro_group_span", since = "1.55.0")]
759 pub fn span_open(&self) -> Span {
760 Span(self.0.span_open())
763 /// Returns the span pointing to the closing delimiter of this group.
766 /// pub fn span_close(&self) -> Span {
769 #[stable(feature = "proc_macro_group_span", since = "1.55.0")]
770 pub fn span_close(&self) -> Span {
771 Span(self.0.span_close())
774 /// Configures the span for this `Group`'s delimiters, but not its internal
777 /// This method will **not** set the span of all the internal tokens spanned
778 /// by this group, but rather it will only set the span of the delimiter
779 /// tokens at the level of the `Group`.
780 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
781 pub fn set_span(&mut self, span: Span) {
782 self.0.set_span(span.0);
786 // N.B., the bridge only provides `to_string`, implement `fmt::Display`
787 // based on it (the reverse of the usual relationship between the two).
788 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
789 impl ToString for Group {
790 fn to_string(&self) -> String {
791 TokenStream::from(TokenTree::from(self.clone())).to_string()
795 /// Prints the group as a string that should be losslessly convertible back
796 /// into the same group (modulo spans), except for possibly `TokenTree::Group`s
797 /// with `Delimiter::None` delimiters.
798 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
799 impl fmt::Display for Group {
800 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
801 f.write_str(&self.to_string())
805 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
806 impl fmt::Debug for Group {
807 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
808 f.debug_struct("Group")
809 .field("delimiter", &self.delimiter())
810 .field("stream", &self.stream())
811 .field("span", &self.span())
816 /// A `Punct` is a single punctuation character such as `+`, `-` or `#`.
818 /// Multi-character operators like `+=` are represented as two instances of `Punct` with different
819 /// forms of `Spacing` returned.
820 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
822 pub struct Punct(bridge::client::Punct);
824 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
825 impl !Send for Punct {}
826 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
827 impl !Sync for Punct {}
829 /// Describes whether a `Punct` is followed immediately by another `Punct` ([`Spacing::Joint`]) or
830 /// by a different token or whitespace ([`Spacing::Alone`]).
831 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
832 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
834 /// A `Punct` is not immediately followed by another `Punct`.
835 /// E.g. `+` is `Alone` in `+ =`, `+ident` and `+()`.
836 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
838 /// A `Punct` is immediately followed by another `Punct`.
839 /// E.g. `+` is `Joint` in `+=` and `++`.
841 /// Additionally, single quote `'` can join with identifiers to form lifetimes: `'ident`.
842 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
847 /// Creates a new `Punct` from the given character and spacing.
848 /// The `ch` argument must be a valid punctuation character permitted by the language,
849 /// otherwise the function will panic.
851 /// The returned `Punct` will have the default span of `Span::call_site()`
852 /// which can be further configured with the `set_span` method below.
853 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
854 pub fn new(ch: char, spacing: Spacing) -> Punct {
855 Punct(bridge::client::Punct::new(ch, spacing))
858 /// Returns the value of this punctuation character as `char`.
859 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
860 pub fn as_char(&self) -> char {
864 /// Returns the spacing of this punctuation character, indicating whether it's immediately
865 /// followed by another `Punct` in the token stream, so they can potentially be combined into
866 /// a multi-character operator (`Joint`), or it's followed by some other token or whitespace
867 /// (`Alone`) so the operator has certainly ended.
868 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
869 pub fn spacing(&self) -> Spacing {
873 /// Returns the span for this punctuation character.
874 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
875 pub fn span(&self) -> Span {
879 /// Configure the span for this punctuation character.
880 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
881 pub fn set_span(&mut self, span: Span) {
882 self.0 = self.0.with_span(span.0);
886 // N.B., the bridge only provides `to_string`, implement `fmt::Display`
887 // based on it (the reverse of the usual relationship between the two).
888 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
889 impl ToString for Punct {
890 fn to_string(&self) -> String {
891 TokenStream::from(TokenTree::from(self.clone())).to_string()
895 /// Prints the punctuation character as a string that should be losslessly convertible
896 /// back into the same character.
897 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
898 impl fmt::Display for Punct {
899 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
900 f.write_str(&self.to_string())
904 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
905 impl fmt::Debug for Punct {
906 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
907 f.debug_struct("Punct")
908 .field("ch", &self.as_char())
909 .field("spacing", &self.spacing())
910 .field("span", &self.span())
915 #[stable(feature = "proc_macro_punct_eq", since = "1.50.0")]
916 impl PartialEq<char> for Punct {
917 fn eq(&self, rhs: &char) -> bool {
918 self.as_char() == *rhs
922 #[stable(feature = "proc_macro_punct_eq_flipped", since = "1.52.0")]
923 impl PartialEq<Punct> for char {
924 fn eq(&self, rhs: &Punct) -> bool {
925 *self == rhs.as_char()
929 /// An identifier (`ident`).
931 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
932 pub struct Ident(bridge::client::Ident);
935 /// Creates a new `Ident` with the given `string` as well as the specified
937 /// The `string` argument must be a valid identifier permitted by the
938 /// language (including keywords, e.g. `self` or `fn`). Otherwise, the function will panic.
940 /// Note that `span`, currently in rustc, configures the hygiene information
941 /// for this identifier.
943 /// As of this time `Span::call_site()` explicitly opts-in to "call-site" hygiene
944 /// meaning that identifiers created with this span will be resolved as if they were written
945 /// directly at the location of the macro call, and other code at the macro call site will be
946 /// able to refer to them as well.
948 /// Later spans like `Span::def_site()` will allow to opt-in to "definition-site" hygiene
949 /// meaning that identifiers created with this span will be resolved at the location of the
950 /// macro definition and other code at the macro call site will not be able to refer to them.
952 /// Due to the current importance of hygiene this constructor, unlike other
953 /// tokens, requires a `Span` to be specified at construction.
954 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
955 pub fn new(string: &str, span: Span) -> Ident {
956 Ident(bridge::client::Ident::new(string, span.0, false))
959 /// Same as `Ident::new`, but creates a raw identifier (`r#ident`).
960 /// The `string` argument be a valid identifier permitted by the language
961 /// (including keywords, e.g. `fn`). Keywords which are usable in path segments
962 /// (e.g. `self`, `super`) are not supported, and will cause a panic.
963 #[stable(feature = "proc_macro_raw_ident", since = "1.47.0")]
964 pub fn new_raw(string: &str, span: Span) -> Ident {
965 Ident(bridge::client::Ident::new(string, span.0, true))
968 /// Returns the span of this `Ident`, encompassing the entire string returned
969 /// by [`to_string`](Self::to_string).
970 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
971 pub fn span(&self) -> Span {
975 /// Configures the span of this `Ident`, possibly changing its hygiene context.
976 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
977 pub fn set_span(&mut self, span: Span) {
978 self.0 = self.0.with_span(span.0);
982 // N.B., the bridge only provides `to_string`, implement `fmt::Display`
983 // based on it (the reverse of the usual relationship between the two).
984 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
985 impl ToString for Ident {
986 fn to_string(&self) -> String {
987 TokenStream::from(TokenTree::from(self.clone())).to_string()
991 /// Prints the identifier as a string that should be losslessly convertible
992 /// back into the same identifier.
993 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
994 impl fmt::Display for Ident {
995 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
996 f.write_str(&self.to_string())
1000 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1001 impl fmt::Debug for Ident {
1002 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1003 f.debug_struct("Ident")
1004 .field("ident", &self.to_string())
1005 .field("span", &self.span())
1010 /// A literal string (`"hello"`), byte string (`b"hello"`),
1011 /// character (`'a'`), byte character (`b'a'`), an integer or floating point number
1012 /// with or without a suffix (`1`, `1u8`, `2.3`, `2.3f32`).
1013 /// Boolean literals like `true` and `false` do not belong here, they are `Ident`s.
1015 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1016 pub struct Literal(bridge::client::Literal);
1018 macro_rules! suffixed_int_literals {
1019 ($($name:ident => $kind:ident,)*) => ($(
1020 /// Creates a new suffixed integer literal with the specified value.
1022 /// This function will create an integer like `1u32` where the integer
1023 /// value specified is the first part of the token and the integral is
1024 /// also suffixed at the end.
1025 /// Literals created from negative numbers might not survive round-trips through
1026 /// `TokenStream` or strings and may be broken into two tokens (`-` and positive literal).
1028 /// Literals created through this method have the `Span::call_site()`
1029 /// span by default, which can be configured with the `set_span` method
1031 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1032 pub fn $name(n: $kind) -> Literal {
1033 Literal(bridge::client::Literal::typed_integer(&n.to_string(), stringify!($kind)))
1038 macro_rules! unsuffixed_int_literals {
1039 ($($name:ident => $kind:ident,)*) => ($(
1040 /// Creates a new unsuffixed integer literal with the specified value.
1042 /// This function will create an integer like `1` where the integer
1043 /// value specified is the first part of the token. No suffix is
1044 /// specified on this token, meaning that invocations like
1045 /// `Literal::i8_unsuffixed(1)` are equivalent to
1046 /// `Literal::u32_unsuffixed(1)`.
1047 /// Literals created from negative numbers might not survive rountrips through
1048 /// `TokenStream` or strings and may be broken into two tokens (`-` and positive literal).
1050 /// Literals created through this method have the `Span::call_site()`
1051 /// span by default, which can be configured with the `set_span` method
1053 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1054 pub fn $name(n: $kind) -> Literal {
1055 Literal(bridge::client::Literal::integer(&n.to_string()))
1061 suffixed_int_literals! {
1063 u16_suffixed => u16,
1064 u32_suffixed => u32,
1065 u64_suffixed => u64,
1066 u128_suffixed => u128,
1067 usize_suffixed => usize,
1069 i16_suffixed => i16,
1070 i32_suffixed => i32,
1071 i64_suffixed => i64,
1072 i128_suffixed => i128,
1073 isize_suffixed => isize,
1076 unsuffixed_int_literals! {
1077 u8_unsuffixed => u8,
1078 u16_unsuffixed => u16,
1079 u32_unsuffixed => u32,
1080 u64_unsuffixed => u64,
1081 u128_unsuffixed => u128,
1082 usize_unsuffixed => usize,
1083 i8_unsuffixed => i8,
1084 i16_unsuffixed => i16,
1085 i32_unsuffixed => i32,
1086 i64_unsuffixed => i64,
1087 i128_unsuffixed => i128,
1088 isize_unsuffixed => isize,
1091 /// Creates a new unsuffixed floating-point literal.
1093 /// This constructor is similar to those like `Literal::i8_unsuffixed` where
1094 /// the float's value is emitted directly into the token but no suffix is
1095 /// used, so it may be inferred to be a `f64` later in the compiler.
1096 /// Literals created from negative numbers might not survive rountrips through
1097 /// `TokenStream` or strings and may be broken into two tokens (`-` and positive literal).
1101 /// This function requires that the specified float is finite, for
1102 /// example if it is infinity or NaN this function will panic.
1103 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1104 pub fn f32_unsuffixed(n: f32) -> Literal {
1106 panic!("Invalid float literal {n}");
1108 let mut repr = n.to_string();
1109 if !repr.contains('.') {
1110 repr.push_str(".0");
1112 Literal(bridge::client::Literal::float(&repr))
1115 /// Creates a new suffixed floating-point literal.
1117 /// This constructor will create a literal like `1.0f32` where the value
1118 /// specified is the preceding part of the token and `f32` is the suffix of
1119 /// the token. This token will always be inferred to be an `f32` in the
1121 /// Literals created from negative numbers might not survive rountrips through
1122 /// `TokenStream` or strings and may be broken into two tokens (`-` and positive literal).
1126 /// This function requires that the specified float is finite, for
1127 /// example if it is infinity or NaN this function will panic.
1128 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1129 pub fn f32_suffixed(n: f32) -> Literal {
1131 panic!("Invalid float literal {n}");
1133 Literal(bridge::client::Literal::f32(&n.to_string()))
1136 /// Creates a new unsuffixed floating-point literal.
1138 /// This constructor is similar to those like `Literal::i8_unsuffixed` where
1139 /// the float's value is emitted directly into the token but no suffix is
1140 /// used, so it may be inferred to be a `f64` later in the compiler.
1141 /// Literals created from negative numbers might not survive rountrips through
1142 /// `TokenStream` or strings and may be broken into two tokens (`-` and positive literal).
1146 /// This function requires that the specified float is finite, for
1147 /// example if it is infinity or NaN this function will panic.
1148 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1149 pub fn f64_unsuffixed(n: f64) -> Literal {
1151 panic!("Invalid float literal {n}");
1153 let mut repr = n.to_string();
1154 if !repr.contains('.') {
1155 repr.push_str(".0");
1157 Literal(bridge::client::Literal::float(&repr))
1160 /// Creates a new suffixed floating-point literal.
1162 /// This constructor will create a literal like `1.0f64` where the value
1163 /// specified is the preceding part of the token and `f64` is the suffix of
1164 /// the token. This token will always be inferred to be an `f64` in the
1166 /// Literals created from negative numbers might not survive rountrips through
1167 /// `TokenStream` or strings and may be broken into two tokens (`-` and positive literal).
1171 /// This function requires that the specified float is finite, for
1172 /// example if it is infinity or NaN this function will panic.
1173 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1174 pub fn f64_suffixed(n: f64) -> Literal {
1176 panic!("Invalid float literal {n}");
1178 Literal(bridge::client::Literal::f64(&n.to_string()))
1182 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1183 pub fn string(string: &str) -> Literal {
1184 Literal(bridge::client::Literal::string(string))
1187 /// Character literal.
1188 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1189 pub fn character(ch: char) -> Literal {
1190 Literal(bridge::client::Literal::character(ch))
1193 /// Byte string literal.
1194 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1195 pub fn byte_string(bytes: &[u8]) -> Literal {
1196 Literal(bridge::client::Literal::byte_string(bytes))
1199 /// Returns the span encompassing this literal.
1200 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1201 pub fn span(&self) -> Span {
1205 /// Configures the span associated for this literal.
1206 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1207 pub fn set_span(&mut self, span: Span) {
1208 self.0.set_span(span.0);
1211 /// Returns a `Span` that is a subset of `self.span()` containing only the
1212 /// source bytes in range `range`. Returns `None` if the would-be trimmed
1213 /// span is outside the bounds of `self`.
1214 // FIXME(SergioBenitez): check that the byte range starts and ends at a
1215 // UTF-8 boundary of the source. otherwise, it's likely that a panic will
1216 // occur elsewhere when the source text is printed.
1217 // FIXME(SergioBenitez): there is no way for the user to know what
1218 // `self.span()` actually maps to, so this method can currently only be
1219 // called blindly. For example, `to_string()` for the character 'c' returns
1220 // "'\u{63}'"; there is no way for the user to know whether the source text
1221 // was 'c' or whether it was '\u{63}'.
1222 #[unstable(feature = "proc_macro_span", issue = "54725")]
1223 pub fn subspan<R: RangeBounds<usize>>(&self, range: R) -> Option<Span> {
1224 self.0.subspan(range.start_bound().cloned(), range.end_bound().cloned()).map(Span)
1228 /// Parse a single literal from its stringified representation.
1230 /// In order to parse successfully, the input string must not contain anything
1231 /// but the literal token. Specifically, it must not contain whitespace or
1232 /// comments in addition to the literal.
1234 /// The resulting literal token will have a `Span::call_site()` span.
1236 /// NOTE: some errors may cause panics instead of returning `LexError`. We
1237 /// reserve the right to change these errors into `LexError`s later.
1238 #[stable(feature = "proc_macro_literal_parse", since = "1.54.0")]
1239 impl FromStr for Literal {
1240 type Err = LexError;
1242 fn from_str(src: &str) -> Result<Self, LexError> {
1243 match bridge::client::Literal::from_str(src) {
1244 Ok(literal) => Ok(Literal(literal)),
1245 Err(()) => Err(LexError),
1250 // N.B., the bridge only provides `to_string`, implement `fmt::Display`
1251 // based on it (the reverse of the usual relationship between the two).
1252 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
1253 impl ToString for Literal {
1254 fn to_string(&self) -> String {
1259 /// Prints the literal as a string that should be losslessly convertible
1260 /// back into the same literal (except for possible rounding for floating point literals).
1261 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1262 impl fmt::Display for Literal {
1263 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1264 f.write_str(&self.to_string())
1268 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
1269 impl fmt::Debug for Literal {
1270 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1275 /// Tracked access to environment variables.
1276 #[unstable(feature = "proc_macro_tracked_env", issue = "74690")]
1277 pub mod tracked_env {
1278 use std::env::{self, VarError};
1279 use std::ffi::OsStr;
1281 /// Retrieve an environment variable and add it to build dependency info.
1282 /// Build system executing the compiler will know that the variable was accessed during
1283 /// compilation, and will be able to rerun the build when the value of that variable changes.
1284 /// Besides the dependency tracking this function should be equivalent to `env::var` from the
1285 /// standard library, except that the argument must be UTF-8.
1286 #[unstable(feature = "proc_macro_tracked_env", issue = "74690")]
1287 pub fn var<K: AsRef<OsStr> + AsRef<str>>(key: K) -> Result<String, VarError> {
1288 let key: &str = key.as_ref();
1289 let value = env::var(key);
1290 crate::bridge::client::FreeFunctions::track_env_var(key, value.as_deref().ok());
1295 /// Tracked access to additional files.
1296 #[unstable(feature = "track_path", issue = "73921")]
1297 pub mod tracked_path {
1299 /// Track a file explicitly.
1301 /// Commonly used for tracking asset preprocessing.
1302 #[unstable(feature = "track_path", issue = "73921")]
1303 pub fn path<P: AsRef<str>>(path: P) {
1304 let path: &str = path.as_ref();
1305 crate::bridge::client::FreeFunctions::track_path(path);