impl Debug (3) MultiProduct

This requires that debug_fmt_fields can also cope with tuple elements.

Author: phimuemue

src/adaptors/multi_product.rs

@@ -18,6 +18,14 @@ pub struct MultiProduct<I>(Vec<MultiProductIter<I>>)
     where I: Iterator + Clone,
           I::Item: Clone;
 
+impl<I> std::fmt::Debug for MultiProduct<I>
+where
+    I: Iterator + Clone + std::fmt::Debug,
+    I::Item: Clone + std::fmt::Debug,
+{
+    debug_fmt_fields!(CoalesceBy, 0);
+}
+
 /// Create a new cartesian product iterator over an arbitrary number
 /// of iterators of the same type.
 ///

src/impl_macros.rs

@@ -2,7 +2,7 @@
 //! Implementation's internal macros
 
 macro_rules! debug_fmt_fields {
-    ($tyname:ident, $($($field:ident).+),*) => {
+    ($tyname:ident, $($($field:tt/*TODO ideally we would accept ident or tuple element here*/).+),*) => {
         fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
             f.debug_struct(stringify!($tyname))
                 $(