Non-fatally assert that tts
is empty. Note that this function
returns even when tts
is non-empty, macros that need to stop
compilation should call cx.diagnostic().abort_if_errors()
(this should be done as rarely as possible).
Extracts a string literal from the macro expanded version of expr
,
returning a diagnostic error of err_msg
if expr
is not a string literal.
The returned bool indicates whether an applicable suggestion has already been
added to the diagnostic to avoid emitting multiple suggestions. Err(Err(ErrorGuaranteed))
indicates that an ast error was encountered.
Extracts a string literal from the macro expanded version of expr
,
emitting err_msg
if expr
is not a string literal. This does not stop
compilation on error, merely emits a non-fatal error and returns Err
.
Extracts comma-separated expressions from tts
.
On error, emit it, and return Err
.
Interpreting tts
as a comma-separated sequence of expressions,
expect exactly one string literal, or emit an error and return Err
.
Parse an expression. On error, emit it, advancing to Eof
, and return Err
.
Emit a warning if the item is annotated with the given attribute. This is used to diagnose when
an attribute may have been mistakenly duplicated.