diff --git a/lib/parslet/atoms/base.rb b/lib/parslet/atoms/base.rb
index a43dfdc..e18429a 100644
--- a/lib/parslet/atoms/base.rb
+++ b/lib/parslet/atoms/base.rb
@@ -51,7 +51,7 @@ def parse(io, options={})
     
     # If we haven't consumed the input, then the pattern doesn't match. Try
     # to provide a good error message (even asking down below)
-    if !options[:prefix] && !source.eof?
+    if !options[:prefix] && source.chars_left > 0
       old_pos = source.pos
       Parslet::Cause.format(
         source, old_pos, 
diff --git a/lib/parslet/atoms/re.rb b/lib/parslet/atoms/re.rb
index 8e01c6e..87fe723 100644
--- a/lib/parslet/atoms/re.rb
+++ b/lib/parslet/atoms/re.rb
@@ -25,7 +25,7 @@ def try(source, context)
     
     # No string could be read
     return context.err(self, source, @error_msgs[:premature]) \
-      if source.eof?
+      if source.chars_left < 1
         
     # No match
     return context.err(self, source, @error_msgs[:failed])
diff --git a/lib/parslet/source.rb b/lib/parslet/source.rb
index ade2fd7..3ec14a9 100644
--- a/lib/parslet/source.rb
+++ b/lib/parslet/source.rb
@@ -47,10 +47,6 @@ def chars_left
       @str.size - @pos
     end
     
-    def eof?
-      @pos >= @str.size
-    end
-
     # Position of the parse as a character offset into the original string. 
     # @note: Encodings...
     attr_accessor :pos
diff --git a/spec/parslet/atoms/base_spec.rb b/spec/parslet/atoms/base_spec.rb
index 3e4545a..7c8799d 100644
--- a/spec/parslet/atoms/base_spec.rb
+++ b/spec/parslet/atoms/base_spec.rb
@@ -55,7 +55,7 @@ def unnamed(obj)
       let(:source) { flexmock("source lookalike", 
         :line_and_column => [1,2], 
         :pos => 1, 
-        :eof? => true) }
+        :chars_left => 0) }
       
       it "should not rewrap in a source" do
         flexmock(Parslet::Source).
diff --git a/spec/parslet/source_spec.rb b/spec/parslet/source_spec.rb
index 237f273..c50c11e 100644
--- a/spec/parslet/source_spec.rb
+++ b/spec/parslet/source_spec.rb
@@ -15,14 +15,14 @@
         source.consume(100).should == 'a'*100
       end
     end
-    describe "<- #eof?" do
-      subject { source.eof? }
+    describe "<- #chars_left" do
+      subject { source.chars_left }
   
-      it { should be_false }
+      it { should == 202 }
       context "after depleting the source" do
         before(:each) { source.consume(10000) }
   
-        it { should be_true }
+        it { should == 0 }
       end
     end
     describe "<- #pos" do
@@ -98,7 +98,7 @@
         attr_reader :results
         before(:each) { 
           @results = {}
-          while not source.eof?
+          while source.chars_left>0
             pos = source.pos
             @results[pos] = source.line_and_column
             source.consume(1)
@@ -123,7 +123,7 @@
         end
         it "should give the same results when reading" do
           cur = source.pos = 0
-          while not source.eof?
+          while source.chars_left>0
             source.line_and_column.should == results[cur]
             cur += 1
             source.consume(1)
@@ -148,7 +148,6 @@
       source.consume(1)
       
       source.consume(2)
-      source.eof?.should == true
       source.chars_left.should == 0
     end 
   end