Module proc_macro

proc_macro by exporting just the correct proc_macro API.

This allow to inject an external proc_macro API like proc_macro2, and this is convenient for library that do not implement directly a procedural macro or avoid to include the external dependencies just to mimic the proc_macro API.

The last case is particular useful when the parser is injected inside the procedural macro code, such as the linux kernel

Modules

token_stream

Public implementation details for the TokenStream type, such as iterators.

tracked_envExperimental

Tracked access to environment variables.

tracked_pathExperimental

Tracked access to additional files.

Macros

quoteExperimental

quote!(..) accepts arbitrary tokens and expands into a TokenStream describing the input. For example, quote!(a + b) will produce an expression, that, when evaluated, constructs the TokenStream [Ident("a"), Punct('+', Alone), Ident("b")].

Structs

Group

A delimited token stream.

Ident

An identifier (ident).

LexError

Error returned from TokenStream::from_str.

Literal

A literal string ("hello"), byte string (b"hello"), C string (c"hello"), character ('a'), byte character (b'a'), an integer or floating point number with or without a suffix (1, 1u8, 2.3, 2.3f32). Boolean literals like true and false do not belong here, they are Idents.

Punct

A Punct is a single punctuation character such as +, - or #.

Span

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

TokenStream

The main type provided by this crate, representing an abstract stream of tokens, or, more specifically, a sequence of token trees. The type provides interfaces for iterating over those token trees and, conversely, collecting a number of token trees into one stream.

DiagnosticExperimental

A structure representing a diagnostic message and associated children messages.

ExpandErrorExperimental

Error returned from TokenStream::expand_expr.

Enums

Delimiter

Describes how a sequence of token trees is delimited.

Spacing

Indicates whether a Punct token can join with the following token to form a multi-character operator.

TokenTree

A single token or a delimited sequence of token trees (e.g., [1, (), ..]).

ConversionErrorKindExperimental

Errors returned when trying to retrieve a literal unescaped value.

EscapeError

Errors and warnings that can occur during string, char, and byte unescaping.

LevelExperimental

An enum representing a diagnostic level.

Traits

MultiSpanExperimental

Trait implemented by types that can be converted into a set of Spans.

ToTokensExperimental

Types that can be interpolated inside a quote! invocation.

Functions

is_available

Determines whether proc_macro has been made accessible to the currently running program.

quoteExperimental

Quote a TokenStream into a TokenStream. This is the actual implementation of the quote!() proc macro.

quote_spanExperimental

Quote a Span into a TokenStream. This is needed to implement a custom quoter.