Suggest correct comparison against negative literal

When parsing as emplacement syntax (`x<-1`), suggest the correct syntax
for comparison against a negative value (`x< -1`).

1 files changed, 10 insertions, 0 deletions

diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index 53465c071f3..07e22b02c55 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -1298,6 +1298,16 @@ impl LitKind {
         }
     }
 
+    /// Returns true if this is a numeric literal.
+    pub fn is_numeric(&self) -> bool {
+        match *self {
+            LitKind::Int(..) |
+            LitKind::Float(..) |
+            LitKind::FloatUnsuffixed(..) => true,
+            _ => false,
+        }
+    }
+
     /// Returns true if this literal has no suffix. Note: this will return true
     /// for literals with prefixes such as raw strings and byte strings.
     pub fn is_unsuffixed(&self) -> bool {