diff --git a/.gitignore b/.gitignore
index 875204c..d7a8809 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,11 @@
 .idea
+.project
+.settings
+.pydevproject
 MANIFEST
 *.pyc
 .tox
 build/
+clint.egg-info/
+dist/
+
diff --git a/AUTHORS b/AUTHORS
index 9776068..4fe6b97 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -29,3 +29,4 @@ Patches and Suggestions
 - Justin Barber <barber.justin (at) gmail>
 - Dmitry Medvinsky
 - Eric Anderson
+- Joshua Richardson
diff --git a/clint/textui/progress.py b/clint/textui/progress.py
index 3ac2298..998bb92 100644
--- a/clint/textui/progress.py
+++ b/clint/textui/progress.py
@@ -33,43 +33,78 @@ ETA_INTERVAL = 1
 #How many intervals (excluding the current one) to calculate the simple moving average
 ETA_SMA_WINDOW = 9
 
-def bar(it, label='', width=32, hide=HIDE_DEFAULT, empty_char=BAR_EMPTY_CHAR, filled_char=BAR_FILLED_CHAR, expected_size=None, every=1):
-    """Progress iterator. Wrap your iterables with it."""
-
-    def _show(_i):
-        if (time.time() - bar.etadelta) > ETA_INTERVAL:
-            bar.etadelta = time.time()
-            bar.ittimes = bar.ittimes[-ETA_SMA_WINDOW:]+[-(bar.start-time.time())/(_i+1)]
-            bar.eta = sum(bar.ittimes)/float(len(bar.ittimes)) * (count-_i)
-            bar.etadisp = time.strftime('%H:%M:%S', time.gmtime(bar.eta))
-        x = int(width*_i/count)
-        if not hide:
-            if ((_i % every)==0 or         # True every "every" updates
-                (_i == count)):            # And when we're done
+class Bar(object):
+    def __enter__(self):
+        return self
+    
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        self.done()
+        return False # we're not surpressing exceptions
+    
+    def __init__(self, label='', width=32, hide=None, empty_char=BAR_EMPTY_CHAR,
+                 filled_char=BAR_FILLED_CHAR, expected_size=None, every=1):
+        self.label = label
+        self.width = width
+        self.hide = hide
+        if hide is None:
+            try:
+                self.hide = not STREAM.isatty()
+            except AttributeError:  # output does not support isatty()
+                self.hide = True                
+        self.empty_char =    empty_char
+        self.filled_char =   filled_char
+        self.expected_size = expected_size
+        self.every =         every
+        self.start =         time.time()
+        self.ittimes =       []
+        self.eta =           0
+        self.etadelta =      time.time()
+        self.etadisp =       time.strftime('%H:%M:%S', time.gmtime(self.eta))
+        if (self.expected_size):
+            self.show(0)
+        
+    def show(self, progress, count=None):
+        if count is not None:
+            self.expected_size = count
+        if self.expected_size is None:
+            raise Exception("expected_size not initialized")
+        if (time.time() - self.etadelta) > ETA_INTERVAL:
+            self.etadelta = time.time()
+            self.ittimes = \
+                self.ittimes[-ETA_SMA_WINDOW:]+\
+                    [-(self.start-time.time())/(progress+1)]
+            self.eta = \
+                sum(self.ittimes)/float(len(self.ittimes)) * \
+                (self.expected_size-progress)
+            self.etadisp = time.strftime('%H:%M:%S', time.gmtime(self.eta))
+        x = int(self.width*progress/self.expected_size)
+        if not self.hide:
+            if ((progress % self.every)==0 or      # True every "every" updates
+                (progress == self.expected_size)): # And when we're done
                 STREAM.write(BAR_TEMPLATE % (
-                    label, filled_char*x, empty_char*(width-x), _i, count, bar.etadisp))
+                    self.label, self.filled_char*x,
+                    self.empty_char*(self.width-x), progress,
+                    self.expected_size, self.etadisp))
                 STREAM.flush()
 
-    count = len(it) if expected_size is None else expected_size
-
-    bar.start    = time.time()
-    bar.ittimes  = []
-    bar.eta      = 0
-    bar.etadelta = time.time()
-    bar.etadisp  = time.strftime('%H:%M:%S', time.gmtime(bar.eta))
-
-    if count:
-        _show(0)
-
-    for i, item in enumerate(it):
-
-        yield item
-        _show(i+1)
-
-    if not hide:
+    def done(self):
+        if not self.hide:
             STREAM.write('\n')
             STREAM.flush()
 
+def bar(it, label='', width=32, hide=HIDE_DEFAULT, empty_char=BAR_EMPTY_CHAR, filled_char=BAR_FILLED_CHAR, expected_size=None, every=1):
+    """Progress iterator. Wrap your iterables with it."""
+
+    count = len(it) if expected_size is None else expected_size
+    
+    with Bar(label=label, width=width, hide=hide, empty_char=BAR_EMPTY_CHAR,
+              filled_char=BAR_FILLED_CHAR, expected_size=count, every=every) \
+              as bar:
+
+        for i, item in enumerate(it):
+    
+            yield item
+            bar.show(i+1)
 
 def dots(it, label='', hide=HIDE_DEFAULT, every=1):
     """Progress iterator. Prints a dot for each item being iterated"""
diff --git a/examples/progressbar.py b/examples/progressbar.py
index 26030e4..a41b6ef 100755
--- a/examples/progressbar.py
+++ b/examples/progressbar.py
@@ -14,6 +14,13 @@ from clint.textui import progress
 if __name__ == '__main__':
     for i in progress.bar(range(100)):
         sleep(random() * 0.2)
+        
+    with progress.Bar(label="nonlinear", expected_size=10) as bar:
+        last_val = 0
+        for val in (1,2,3,9,10):
+            sleep(2 * (val - last_val))
+            bar.show(val)
+            last_val = val
 
     for i in progress.dots(range(100)):
         sleep(random() * 0.2)