Function rustc_expand::mbe::macro_rules::emit_frag_parse_err

fn emit_frag_parse_err(
    e: DiagnosticBuilder<'_>, 
    parser: &Parser<'_>, 
    orig_parser: &mut Parser<'_>, 
    site_span: Span, 
    arm_span: Span, 
    kind: AstFragmentKind
)