rollup merge of #20269: dirk/indent-where

* Add <span class=‘where’> around clause
* CSS rule to format the span

(for issue #20176)

Author: alexcrichton

src/librustdoc/html/format.rs

@@ -120,7 +120,7 @@ impl<'a> fmt::Show for WhereClause<'a> {
         if gens.where_predicates.len() == 0 {
             return Ok(());
         }
-        try!(f.write(" where ".as_bytes()));
+        try!(f.write(" <span class='where'>where ".as_bytes()));
         for (i, pred) in gens.where_predicates.iter().enumerate() {
             if i > 0 {
                 try!(f.write(", ".as_bytes()));
@@ -146,6 +146,7 @@ impl<'a> fmt::Show for WhereClause<'a> {
                 }
             }
         }
+        try!(f.write("</span>".as_bytes()));
         Ok(())
     }
 }

src/librustdoc/html/static/main.css

@@ -306,6 +306,11 @@ nav.sub {
     font-size: 1em;
     position: relative;
 }
+/* Shift "where ..." part of method definition down a line */
+.content .method .where { display: block; }
+/* Bit of whitespace to indent it */
+.content .method .where::before { content: '      '; }
+
 .content .methods .docblock { margin-left: 40px; }
 
 .content .impl-items .docblock { margin-left: 40px; }