+ Fixes atoms_spec (and thus most of parslet)

lib/parslet/atoms/base.rb

@@ -194,10 +194,13 @@ def flatten(value, named=false) # :nodoc:
   end
 
   def flatten_sequence(list) # :nodoc:
-    list.compact.inject('') { |r, e|        # and then merge flat elements
+    foldl(list.compact) { |r, e|        # and then merge flat elements
       merge_fold(r, e)
     }
   end
+  def foldl(list, &block)
+    list[1..-1].inject(list.first, &block)
+  end
   def merge_fold(l, r) # :nodoc:
     # equal pairs: merge. 
     if l.class == r.class
@@ -212,8 +215,8 @@ def merge_fold(l, r) # :nodoc:
     # unequal pairs: hoist to same level. 
 
     # special case: If one of them is a string, the other is more important 
-    return l if r.class == String
-    return r if l.class == String
+    return l if r.respond_to? :to_str
+    return r if l.respond_to? :to_str
 
     # otherwise just create an array for one of them to live in 
     return l + [r] if r.class == Hash

lib/parslet/atoms/str.rb

@@ -26,7 +26,7 @@ def try(source, context) # :nodoc:
 
     # Failures: 
     return error(source, @error_msgs[:premature]) unless s && s.size==str.size
-    return error(source, @error_msgs[:failed]+s.inspect, error_pos) 
+    return error(source, @error_msgs[:failed]+s.str.inspect, error_pos) 
   end
 
   def to_s_inner(prec) # :nodoc:

spec/parslet/atoms_spec.rb

@@ -327,7 +327,7 @@ def src(str); Parslet::Source.new str; end
     end
 
     context "(str('a') >> str('ignore') >> str('b')) (no .as(...))" do
-      it "should return an empty subtree" do
+      it "should return simply the original string" do
         (str('a') >> str('ignore') >> str('b')).
           parse('aignoreb').should == 'aignoreb'
       end