Give up evaluating (unary-prefix '-' 0)

Close #117

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    JS, WHY YOU SUCK SO BADLY? ;-(

diff --git a/lib/compress.js b/lib/compress.js
index fe3d34b..ca23c40 100644 (file)
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -628,7 +628,10 @@ merge(Compressor.prototype, {
               case "typeof": return typeof ev(e);
               case "void": return void ev(e);
               case "~": return ~ev(e);
-              case "-": return -ev(e);
+              case "-":
+                e = ev(e);
+                if (e === 0) throw def;
+                return -e;
               case "+": return +ev(e);
             }
             throw def;