added $format default to all .fmt variants

src/classes/Mapping.pir

@@ -28,21 +28,26 @@ src/classes/Mapping.pir - Perl 6 hash class and related functions
 
 =item fmt
 
- our Str multi Mapping::fmt ( Str $format, $separator = "\n" )
+ our Str multi Mapping::fmt ( Str $format = "%s\t%s", $separator = "\n" )
 
 Returns the invocant mapping formatted by an implicit call to C<.fmt> on
 every pair, joined by newlines or an explicitly given separator.
 
 =cut
 
 .sub 'fmt' :method :multi() :subid('mapping_fmt')
-    .param pmc format
-    .param string sep  :optional
-    .param int has_sep :opt_flag
+    .param string format  :optional
+    .param int has_format :opt_flag
+    .param string sep     :optional
+    .param int has_sep    :opt_flag
 
     .local pmc it
     .local pmc rv
 
+    if has_format goto have_format
+    format = "%s\t%s"
+
+  have_format:
     if has_sep goto have_sep
     sep = "\n"
 

src/setting/Any-str.pm

@@ -15,7 +15,7 @@ class Any is also {
         self.substr(0, -1)
     }
 
-    our Str multi method fmt(Str $format) {
+    our Str multi method fmt(Str $format = '%s') {
         sprintf($format, self)
     }
 

src/setting/List.pm

@@ -2,13 +2,13 @@ class List is also {
 
 =begin item fmt
 
- our Str multi List::fmt ( Str $format, $separator = ' ' )
+ our Str multi List::fmt ( Str $format = '%s', $separator = ' ' )
 
 Returns the invocant list formatted by an implicit call to C<sprintf> on each
 of the elements, then joined with spaces or an explicitly given separator.
 
 =end item
-    multi method fmt(Str $format, $sep = ' ') is export {
+    multi method fmt(Str $format = '%s', $sep = ' ') is export {
         return join($sep, self.map({ sprintf($format, $^elem) }));
     }
 

src/setting/Pair.pm

@@ -13,13 +13,13 @@ Delegates on to a method call '.:Xkey(Xval)'.
 
 =begin item fmt
 
-  our Str multi Pair::fmt ( Str $format )
+  our Str multi Pair::fmt ( Str $format = "%s\t%s" )
 
 Returns the invocant pair formatted by an implicit call to C<sprintf> on
 the key and value.
 
 =end item
-    method fmt(Str $format) {
+    method fmt(Str $format = "%s\t%s") {
         return sprintf($format, $.key, $.value);
     }