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Update links (#472)

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Yuki Okushi 2019-10-18 16:22:17 +09:00 committed by GitHub
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src/macro-expansion.md
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@ -7,7 +7,7 @@ before name resolution, macros are expanded using these portions of the code.
The macro parser, in turn, may call the normal Rust parser when it needs to
bind a metavariable (e.g. `$my_expr`) while parsing the contents of a macro
invocation. The code for macro expansion is in
[`src/libsyntax/ext/mbe/`][code_dir]. This chapter aims to explain how macro
[`src/libsyntax_expand/mbe/`][code_dir]. This chapter aims to explain how macro
expansion works.
### Example
@ -61,7 +61,7 @@ invocations. Interestingly, both are done by the macro parser.
Basically, the macro parser is like an NFA-based regex parser. It uses an
algorithm similar in spirit to the [Earley parsing
algorithm](https://en.wikipedia.org/wiki/Earley_parser). The macro parser is
defined in [`src/libsyntax/ext/mbe/macro_parser.rs`][code_mp].
defined in [`src/libsyntax_expand/mbe/macro_parser.rs`][code_mp].
The interface of the macro parser is as follows (this is slightly simplified):
@ -110,7 +110,7 @@ normal Rust parser.
As mentioned above, both definitions and invocations of macros are parsed using
the macro parser. This is extremely non-intuitive and self-referential. The code
to parse macro _definitions_ is in
[`src/libsyntax/ext/mbe/macro_rules.rs`][code_mr]. It defines the pattern for
[`src/libsyntax_expand/mbe/macro_rules.rs`][code_mr]. It defines the pattern for
matching for a macro definition as `$( $lhs:tt => $rhs:tt );+`. In other words,
a `macro_rules` definition should have in its body at least one occurrence of a
token tree followed by `=>` followed by another token tree. When the compiler
@ -139,7 +139,7 @@ the parse is ambiguous, while if there are no matches at all, there is a syntax
error.
For more information about the macro parser's implementation, see the comments
in [`src/libsyntax/ext/mbe/macro_parser.rs`][code_mp].
in [`src/libsyntax_expand/mbe/macro_parser.rs`][code_mp].
### Hygiene
@ -205,8 +205,8 @@ TODO
TODO: maybe something about macros 2.0?
[code_dir]: https://github.com/rust-lang/rust/tree/master/src/libsyntax/ext/mbe
[code_mp]: https://doc.rust-lang.org/nightly/nightly-rustc/syntax/ext/mbe/macro_parser
[code_mr]: https://doc.rust-lang.org/nightly/nightly-rustc/syntax/ext/mbe/macro_rules
[code_parse_int]: https://doc.rust-lang.org/nightly/nightly-rustc/syntax/ext/mbe/macro_parser/fn.parse.html
[code_dir]: https://github.com/rust-lang/rust/tree/master/src/libsyntax_expand/mbe
[code_mp]: https://doc.rust-lang.org/nightly/nightly-rustc/syntax_expand/mbe/macro_parser
[code_mr]: https://doc.rust-lang.org/nightly/nightly-rustc/syntax_expand/mbe/macro_rules
[code_parse_int]: https://doc.rust-lang.org/nightly/nightly-rustc/syntax_expand/mbe/macro_parser/fn.parse.html
[parsing]: ./the-parser.html