From 5cf9f6330a02a0e86f08223289c74b36fba784db Mon Sep 17 00:00:00 2001 From: est31 Date: Thu, 10 Aug 2017 01:42:36 +0200 Subject: Add a feature gate @alexcrichton figured out a way how to do it :) --- src/libsyntax/ext/source_util.rs | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'src/libsyntax/ext') diff --git a/src/libsyntax/ext/source_util.rs b/src/libsyntax/ext/source_util.rs index 3cdd3a4b2c3..b293aa8de38 100644 --- a/src/libsyntax/ext/source_util.rs +++ b/src/libsyntax/ext/source_util.rs @@ -52,6 +52,16 @@ pub fn expand_column(cx: &mut ExtCtxt, sp: Span, tts: &[tokenstream::TokenTree]) base::MacEager::expr(cx.expr_u32(topmost, loc.col.to_usize() as u32)) } +/* __rust_unstable_column!(): expands to the current column number */ +pub fn expand_column_gated(cx: &mut ExtCtxt, sp: Span, tts: &[tokenstream::TokenTree]) + -> Box { + if sp.allows_unstable() { + expand_column(cx, sp, tts) + } else { + cx.span_fatal(sp, "the __rust_unstable_column macro is unstable"); + } +} + /// file!(): expands to the current filename */ /// The filemap (`loc.file`) contains a bunch more information we could spit /// out if we wanted. -- cgit 1.4.1-3-g733a5