Module syntax::ext::tt::macro_rules

🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?

Structs

FirstSets	[ Experimental ]
MacroRulesMacroExpander	[ Experimental ]
ParserAnyMacro	[ Experimental ]
TokenSet	[ Experimental ]

Functions

check_lhs_no_empty_seq	[ Experimental ] Check that the lhs contains no repetition which could match an empty token tree, because then the matcher would hang indefinitely.
check_lhs_nt_follows	[ Experimental ]
check_matcher	[ Experimental ]
check_matcher_core	[ Experimental ]
check_rhs	[ Experimental ]
compile	[ Experimental ] Converts a macro_rules! invocation into a syntax extension.
frag_can_be_followed_by_any	[ Experimental ] True if a fragment of type frag can be followed by any sort of token. We use this (among other things) as a useful approximation for when frag can be followed by a repetition like $(...)* or $(...)+. In general, these can be a bit tricky to reason about, so we adopt a conservative position that says that any fragment specifier which consumes at most one token tree can be followed by a fragment specifier (indeed, these fragments can be followed by ANYTHING without fear of future compatibility hazards).
generic_extension	[ Experimental ] Given lhses and rhses, this is the new macro we create
has_legal_fragment_specifier	[ Experimental ]
is_in_follow	[ Experimental ] True if frag can legally be followed by the token tok. For fragments that can consume an unbounded number of tokens, tok must be within a well-defined follow set. This is intended to guarantee future compatibility: for example, without this rule, if we expanded expr to include a new binary operator, we might break macros that were relying on that binary operator as a separator.
is_legal_fragment_specifier	[ Experimental ]
quoted_tt_to_string	[ Experimental ]
token_can_be_followed_by_any	[ Experimental ]
trace_macros_note	[ Experimental ]