Merge branch 'mergeme/grc/cross_platform_work'

22 files changed, 146 insertions, 149 deletions

diff --git a/grc/Makefile.am b/grc/Makefile.am
index c36786281..9d473b4d3 100644
--- a/grc/Makefile.am
+++ b/grc/Makefile.am
@@ -43,7 +43,6 @@ BUILT_SOURCES += grc.conf
 
 grc.conf: $(srcdir)/grc.conf.in Makefile
 	sed \
-		-e 's|@pythonw[@]|$(PYTHONW)|g' \
 		-e 's|@blocksdir[@]|$(grc_blocksdir)|g' \
 		-e 's|@docdir[@]|$(gr_docdir)|g' \
 	$< > $@
diff --git a/grc/base/Block.py b/grc/base/Block.py
index 42eb6b3fb..fe7ad3c2f 100644
--- a/grc/base/Block.py
+++ b/grc/base/Block.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -92,8 +92,8 @@ class Block(Element):
 		for param in map(lambda n: self.get_parent().get_parent().Param(block=self, n=n), params):
 			key = param.get_key()
 			#test against repeated keys
-			try: assert key not in self.get_param_keys()
-			except AssertionError: raise Exception, 'Key "%s" already exists in params'%key
+			if key in self.get_param_keys():
+				raise Exception, 'Key "%s" already exists in params'%key
 			#store the param
 			self.get_params().append(param)
 		#create the source objects
@@ -101,8 +101,8 @@ class Block(Element):
 		for source in map(lambda n: self.get_parent().get_parent().Port(block=self, n=n, dir='source'), sources):
 			key = source.get_key()
 			#test against repeated keys
-			try: assert key not in self.get_source_keys()
-			except AssertionError: raise Exception, 'Key "%s" already exists in sources'%key
+			if key in self.get_source_keys():
+				raise Exception, 'Key "%s" already exists in sources'%key
 			#store the port
 			self.get_sources().append(source)
 		#create the sink objects
@@ -110,8 +110,8 @@ class Block(Element):
 		for sink in map(lambda n: self.get_parent().get_parent().Port(block=self, n=n, dir='sink'), sinks):
 			key = sink.get_key()
 			#test against repeated keys
-			try: assert key not in self.get_sink_keys()
-			except AssertionError: raise Exception, 'Key "%s" already exists in sinks'%key
+			if key in self.get_sink_keys():
+				raise Exception, 'Key "%s" already exists in sinks'%key
 			#store the port
 			self.get_sinks().append(sink)
 
diff --git a/grc/base/Connection.py b/grc/base/Connection.py
index 94d4751b2..3ce7fd07f 100644
--- a/grc/base/Connection.py
+++ b/grc/base/Connection.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -37,10 +37,12 @@ class Connection(Element):
 		for port in (porta, portb):
 			if port.is_source(): source = port
 			if port.is_sink(): sink = port
-		assert(source and sink)
+		if not source: raise ValueError('Connection could not isolate source')
+		if not sink: raise ValueError('Connection could not isolate sink')
 		#ensure that this connection (source -> sink) is unique
 		for connection in self.get_parent().get_connections():
-			assert not (connection.get_source() is source and connection.get_sink() is sink)
+			if connection.get_source() is source and connection.get_sink() is sink:
+				raise Exception('This connection between source and sink is not unique.')
 		self._source = source
 		self._sink = sink
 
@@ -62,8 +64,8 @@ class Connection(Element):
 		Element.validate(self)
 		source_type = self.get_source().get_type()
 		sink_type = self.get_sink().get_type()
-		try: assert source_type == sink_type
-		except AssertionError: self.add_error_message('Source type "%s" does not match sink type "%s".'%(source_type, sink_type))
+		if source_type != sink_type:
+			self.add_error_message('Source type "%s" does not match sink type "%s".'%(source_type, sink_type))
 
 	def get_enabled(self):
 		"""
diff --git a/grc/base/FlowGraph.py b/grc/base/FlowGraph.py
index b4ac8fc3a..0ba1f2389 100644
--- a/grc/base/FlowGraph.py
+++ b/grc/base/FlowGraph.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -194,18 +194,26 @@ class FlowGraph(Element):
 				sink_key = connection_n.find('sink_key')
 				#verify the blocks
 				block_ids = map(lambda b: b.get_id(), self.get_blocks())
-				assert(source_block_id in block_ids)
-				assert(sink_block_id in block_ids)
+				if source_block_id not in block_ids:
+					raise LookupError('source block id "%s" not in block ids'%source_block_id)
+				if sink_block_id not in block_ids:
+					raise LookupError('sink block id "%s" not in block ids'%sink_block_id)
 				#get the blocks
 				source_block = self.get_block(source_block_id)
 				sink_block = self.get_block(sink_block_id)
 				#verify the ports
-				assert(source_key in source_block.get_source_keys())
-				assert(sink_key in sink_block.get_sink_keys())
+				if source_key not in source_block.get_source_keys():
+					raise LookupError('source key "%s" not in source block keys'%source_key)
+				if sink_key not in sink_block.get_sink_keys():
+					raise LookupError('sink key "%s" not in sink block keys'%sink_key)
 				#get the ports
 				source = source_block.get_source(source_key)
 				sink = sink_block.get_sink(sink_key)
 				#build the connection
 				self.connect(source, sink)
-			except AssertionError: Messages.send_error_load('Connection between %s(%s) and %s(%s) could not be made.'%(source_block_id, source_key, sink_block_id, sink_key))
+			except LookupError, e: Messages.send_error_load(
+				'Connection between %s(%s) and %s(%s) could not be made.\n\t%s'%(
+					source_block_id, source_key, sink_block_id, sink_key, e
+				)
+			)
 		self.rewrite() #global rewrite
diff --git a/grc/base/Param.py b/grc/base/Param.py
index 5cd0f9d6d..c2fa5461a 100644
--- a/grc/base/Param.py
+++ b/grc/base/Param.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -34,16 +34,16 @@ class Option(Element):
 		self._opts = dict()
 		opts = n.findall('opt')
 		#test against opts when non enum
-		try: assert self.get_parent().is_enum() or not opts
-		except AssertionError: raise Exception, 'Options for non-enum types cannot have sub-options'
+		if not self.get_parent().is_enum() and opts:
+			raise Exception, 'Options for non-enum types cannot have sub-options'
 		#extract opts
 		for opt in opts:
 			#separate the key:value
 			try: key, value = opt.split(':')
 			except: raise Exception, 'Error separating "%s" into key:value'%opt
 			#test against repeated keys
-			try: assert not self._opts.has_key(key)
-			except AssertionError: raise Exception, 'Key "%s" already exists in option'%key
+			if self._opts.has_key(key):
+				raise Exception, 'Key "%s" already exists in option'%key
 			#store the option
 			self._opts[key] = value
 
@@ -79,24 +79,24 @@ class Param(Element):
 		for option in map(lambda o: Option(param=self, n=o), n.findall('option')):
 			key = option.get_key()
 			#test against repeated keys
-			try: assert key not in self.get_option_keys()
-			except AssertionError: raise Exception, 'Key "%s" already exists in options'%key
+			if key in self.get_option_keys():
+				raise Exception, 'Key "%s" already exists in options'%key
 			#store the option
 			self.get_options().append(option)
 		#test the enum options
 		if self.is_enum():
 			#test against options with identical keys
-			try: assert len(set(self.get_option_keys())) == len(self.get_options())
-			except AssertionError: raise Exception, 'Options keys "%s" are not unique.'%self.get_option_keys()
+			if len(set(self.get_option_keys())) != len(self.get_options()):
+				raise Exception, 'Options keys "%s" are not unique.'%self.get_option_keys()
 			#test against inconsistent keys in options
 			opt_keys = self.get_options()[0].get_opt_keys()
 			for option in self.get_options():
-				try: assert set(opt_keys) == set(option.get_opt_keys())
-				except AssertionError: raise Exception, 'Opt keys "%s" are not identical across all options.'%opt_keys
+				if set(opt_keys) != set(option.get_opt_keys()):
+					raise Exception, 'Opt keys "%s" are not identical across all options.'%opt_keys
 			#if a value is specified, it must be in the options keys
 			self._value = value if value or value in self.get_option_keys() else self.get_option_keys()[0]
-			try: assert self.get_value() in self.get_option_keys()
-			except AssertionError: raise Exception, 'The value "%s" is not in the possible values of "%s".'%(self.get_value(), self.get_option_keys())
+			if self.get_value() not in self.get_option_keys():
+				raise Exception, 'The value "%s" is not in the possible values of "%s".'%(self.get_value(), self.get_option_keys())
 		else: self._value = value or ''
 
 	def validate(self):
@@ -105,8 +105,8 @@ class Param(Element):
 		The value must be evaluated and type must a possible type.
 		"""
 		Element.validate(self)
-		try: assert self.get_type() in self.get_types()
-		except AssertionError: self.add_error_message('Type "%s" is not a possible type.'%self.get_type())
+		if self.get_type() not in self.get_types():
+			self.add_error_message('Type "%s" is not a possible type.'%self.get_type())
 
 	def get_evaluated(self): raise NotImplementedError
 
diff --git a/grc/base/Platform.py b/grc/base/Platform.py
index 096fdec41..a66c28ab9 100644
--- a/grc/base/Platform.py
+++ b/grc/base/Platform.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009, 2011 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -17,16 +17,6 @@ along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 """
 
-#Perform python integrity checks:
-# GRC will not work with interpreters that fail the checks below.
-# This can fail on interpreters built with special optimizations.
-try:
-	assert False
-	raise Exception, 'Failed python integrity check: assert not supported'
-except AssertionError: pass
-if __doc__ is None:
-	raise Exception, 'Failed python integrity check: __doc__ not supported'
-
 import os
 import sys
 from .. base import ParseXML, odict
@@ -91,13 +81,12 @@ class Platform(_Element):
 				block = self.Block(self._flow_graph, n)
 				key = block.get_key()
 				#test against repeated keys
-				try:
-					assert key not in self.get_block_keys()
-					#store the block
+				if key in self.get_block_keys():
+					print >> sys.stderr, 'Warning: Block with key "%s" already exists.\n\tIgnoring: %s'%(key, xml_file)
+				#store the block
+				else:
 					self._blocks[key] = block
 					self._blocks_n[key] = n
-				except AssertionError:
-					print >> sys.stderr, 'Warning: Block with key "%s" already exists.\n\tIgnoring: %s'%(key, xml_file)
 			except ParseXML.XMLSyntaxError, e: 
 				try: #try to add the xml file as a block tree
 					ParseXML.validate_dtd(xml_file, BLOCK_TREE_DTD)
diff --git a/grc/base/Port.py b/grc/base/Port.py
index 494ea894f..7a1b5d4e6 100644
--- a/grc/base/Port.py
+++ b/grc/base/Port.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -42,8 +42,8 @@ class Port(Element):
 		The port must be non-empty and type must a possible type.
 		"""
 		Element.validate(self)
-		try: assert self.get_type() in self.get_types()
-		except AssertionError: self.add_error_message('Type "%s" is not a possible type.'%self.get_type())
+		if self.get_type() not in self.get_types():
+			self.add_error_message('Type "%s" is not a possible type.'%self.get_type())
 
 	def __str__(self):
 		if self.is_source():
diff --git a/grc/base/odict.py b/grc/base/odict.py
index ac3cb2070..044d04ad7 100644
--- a/grc/base/odict.py
+++ b/grc/base/odict.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -55,7 +55,7 @@ class odict(DictMixin):
 		@param val the value for the new entry
 		"""
 		index = (pos_key is None) and len(self._keys) or self._keys.index(pos_key)
-		assert key not in self._keys
+		if key in self._keys: raise KeyError('Cannot insert, key "%s" already exists'%str(key))
 		self._keys.insert(index+1, key)
 		self._data[key] = val
 
@@ -67,8 +67,8 @@ class odict(DictMixin):
 		@param key the key for the new entry
 		@param val the value for the new entry
 		"""
-		index = (pos_key is not None) and self._keys.index(pos_key) or 0 
-		assert key not in self._keys
+		index = (pos_key is not None) and self._keys.index(pos_key) or 0
+		if key in self._keys: raise KeyError('Cannot insert, key "%s" already exists'%str(key))
 		self._keys.insert(index, key)
 		self._data[key] = val
 
diff --git a/grc/grc.conf.in b/grc/grc.conf.in
index 37a049971..9363ca981 100644
--- a/grc/grc.conf.in
+++ b/grc/grc.conf.in
@@ -3,7 +3,6 @@
 # ~/.gnuradio/config.conf
 
 [grc]
-pythonw = @pythonw@
 doc_dir = @docdir@
 global_blocks_path = @blocksdir@
 local_blocks_path =
diff --git a/grc/gui/ActionHandler.py b/grc/gui/ActionHandler.py
index 350b297bb..15785f2ee 100644
--- a/grc/gui/ActionHandler.py
+++ b/grc/gui/ActionHandler.py
@@ -1,5 +1,5 @@
 """
-Copyright 2007, 2008, 2009, 2011 Free Software Foundation, Inc.
+Copyright 2007-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -78,8 +78,7 @@ class ActionHandler:
 		When not in focus, gtk and the accelerators handle the the key press.
 		@return false to let gtk handle the key action
 		"""
-		try: assert self.get_focus_flag()
-		except AssertionError: return False
+		if not self.get_focus_flag(): return False
 		return Actions.handle_key_press(event)
 
 	def _quit(self, window, event):
diff --git a/grc/gui/Actions.py b/grc/gui/Actions.py
index f374efde1..4d196477e 100644
--- a/grc/gui/Actions.py
+++ b/grc/gui/Actions.py
@@ -1,5 +1,5 @@
 """
-Copyright 2007, 2008, 2009 Free Software Foundation, Inc.
+Copyright 2007-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -76,7 +76,8 @@ class Action(gtk.Action):
 		for i in range(len(keypresses)/2):
 			keyval, mod_mask = keypresses[i*2:(i+1)*2]
 			#register this keypress
-			assert not _actions_keypress_dict.has_key((keyval, mod_mask))
+			if _actions_keypress_dict.has_key((keyval, mod_mask)):
+				raise KeyError('keyval/mod_mask pair already registered "%s"'%str((keyval, mod_mask)))
 			_actions_keypress_dict[(keyval, mod_mask)] = self
 			#set the accelerator group, and accelerator path
 			#register the key name and mod mask with the accelerator path
diff --git a/grc/gui/FlowGraph.py b/grc/gui/FlowGraph.py
index 897145a1d..9f3326ada 100644
--- a/grc/gui/FlowGraph.py
+++ b/grc/gui/FlowGraph.py
@@ -1,5 +1,5 @@
 """
-Copyright 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+Copyright 2007-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -290,10 +290,10 @@ class FlowGraph(Element):
 		for selected in selected_elements:
 			if selected in elements: continue
 			selected_elements.remove(selected)
-		try: assert self._old_selected_port.get_parent() in elements
-		except: self._old_selected_port = None
-		try: assert self._new_selected_port.get_parent() in elements
-		except: self._new_selected_port = None
+		if self._old_selected_port and self._old_selected_port.get_parent() not in elements:
+			self._old_selected_port = None
+		if self._new_selected_port and self._new_selected_port.get_parent() not in elements:
+			self._new_selected_port = None
 		#update highlighting
 		for element in elements:
 			element.set_highlighted(element in selected_elements)
diff --git a/grc/gui/Utils.py b/grc/gui/Utils.py
index b5489d56e..bb19ed3d9 100644
--- a/grc/gui/Utils.py
+++ b/grc/gui/Utils.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -53,7 +53,8 @@ def get_rotated_coordinate(coor, rotation):
 	"""
 	#handles negative angles
 	rotation = (rotation + 360)%360
-	assert rotation in POSSIBLE_ROTATIONS
+	if rotation not in POSSIBLE_ROTATIONS:
+		raise ValueError('unusable rotation angle "%s"'%str(rotation))
 	#determine the number of degrees to rotate
 	cos_r, sin_r = {
 		0: (1, 0),
diff --git a/grc/python/Block.py b/grc/python/Block.py
index bd03eb5cd..14a5859e4 100644
--- a/grc/python/Block.py
+++ b/grc/python/Block.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -65,9 +65,8 @@ class Block(_Block, _GUIBlock):
 		for check in self._checks:
 			check_res = self.resolve_dependencies(check)
 			try:
-				check_eval = self.get_parent().evaluate(check_res)
-				try: assert check_eval
-				except AssertionError: self.add_error_message('Check "%s" failed.'%check)
+				if not self.get_parent().evaluate(check_res):
+					self.add_error_message('Check "%s" failed.'%check)
 			except: self.add_error_message('Check "%s" did not evaluate.'%check)
 
 	def rewrite(self):
@@ -134,9 +133,9 @@ class Block(_Block, _GUIBlock):
 			try:
 				value = param.get_evaluated()
 				value = value + direction
-				assert 0 < value
-				param.set_value(value)
-				changed = True
+				if 0 < value:
+					param.set_value(value)
+					changed = True
 			except: pass
 		return changed
 
diff --git a/grc/python/Connection.py b/grc/python/Connection.py
index edc18841a..39f915740 100644
--- a/grc/python/Connection.py
+++ b/grc/python/Connection.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -38,5 +38,5 @@ class Connection(_Connection, _GUIConnection):
 		#check vector length
 		source_vlen = self.get_source().get_vlen()
 		sink_vlen = self.get_sink().get_vlen()
-		try: assert source_vlen == sink_vlen
-		except AssertionError: self.add_error_message('Source vector length "%s" does not match sink vector length "%s".'%(source_vlen, sink_vlen))
+		if source_vlen != sink_vlen:
+			self.add_error_message('Source vector length "%s" does not match sink vector length "%s".'%(source_vlen, sink_vlen))
diff --git a/grc/python/Constants.py b/grc/python/Constants.py
index e661c3927..868c822aa 100644
--- a/grc/python/Constants.py
+++ b/grc/python/Constants.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -23,10 +23,8 @@ from gnuradio import gr
 
 _gr_prefs = gr.prefs()
 
-PYEXEC = os.environ.get('PYTHONW', _gr_prefs.get_string('grc', 'pythonw', ''))
-
 #setup paths
-PATH_SEP = ':'
+PATH_SEP = {'/':':', '\\':';'}[os.path.sep]
 DOCS_DIR = os.environ.get('GR_DOC_DIR', _gr_prefs.get_string('grc', 'doc_dir', ''))
 HIER_BLOCKS_LIB_DIR = os.path.join(os.path.expanduser('~'), '.grc_gnuradio')
 BLOCKS_DIRS = filter( #filter blank strings
diff --git a/grc/python/Generator.py b/grc/python/Generator.py
index b669fa65a..b31f0a009 100644
--- a/grc/python/Generator.py
+++ b/grc/python/Generator.py
@@ -18,14 +18,14 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 """
 
 import os
+import sys
 import subprocess
 import tempfile
 from Cheetah.Template import Template
 import expr_utils
 from Constants import \
 	TOP_BLOCK_FILE_MODE, HIER_BLOCK_FILE_MODE, \
-	HIER_BLOCKS_LIB_DIR, PYEXEC, \
-	FLOW_GRAPH_TEMPLATE
+	HIER_BLOCKS_LIB_DIR, FLOW_GRAPH_TEMPLATE
 import convert_hier
 from .. gui import Messages
 
@@ -74,10 +74,20 @@ Add a Misc->Throttle block to your flow graph to avoid CPU congestion.''')
 		Execute this python flow graph.
 		@return a popen object
 		"""
-		#execute
-		cmds = [PYEXEC, '-u', self.get_file_path()] #-u is unbuffered stdio
-		if self._generate_options == 'no_gui':
+		#extract the path to the python executable
+		python_exe = sys.executable
+
+		#when using wx gui on mac os, execute with pythonw
+		if self._generate_options == 'wx_gui' and 'darwin' in sys.platform.lower():
+			python_exe += 'w'
+
+		#setup the command args to run
+		cmds = [python_exe, '-u', self.get_file_path()] #-u is unbuffered stdio
+
+		#when in no gui mode on linux, use an xterm (looks nice)
+		if self._generate_options == 'no_gui' and 'linux' in sys.platform.lower():
 			cmds = ['xterm', '-e'] + cmds
+
 		p = subprocess.Popen(args=cmds, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, shell=False, universal_newlines=True)
 		return p
 
diff --git a/grc/python/Param.py b/grc/python/Param.py
index 303ab3ed8..5536138c1 100644
--- a/grc/python/Param.py
+++ b/grc/python/Param.py
@@ -213,8 +213,7 @@ class Param(_Param, _GUIParam):
 			lambda p: p._vlen, self.get_parent().get_ports())
 		):
 			try:
-				assert int(self.get_evaluated()) == 1
-				return 'part'
+				if int(self.get_evaluated()) == 1: return 'part'
 			except: pass
 		#hide empty grid positions
 		if self.get_key() in ('grid_pos', 'notebook') and not self.get_value(): return 'part'
@@ -244,8 +243,7 @@ class Param(_Param, _GUIParam):
 		def eval_string(v):
 			try:
 				e = self.get_parent().get_parent().evaluate(v)
-				assert isinstance(e, str)
-				return e
+				if isinstance(e, str): return e
 			except:
 				self._stringify_flag = True
 				return v
@@ -265,21 +263,21 @@ class Param(_Param, _GUIParam):
 			#raise an exception if the data is invalid
 			if t == 'raw': return e
 			elif t == 'complex':
-				try: assert isinstance(e, COMPLEX_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type complex.'%str(e)
+				if not isinstance(e, COMPLEX_TYPES):
+					raise Exception, 'Expression "%s" is invalid for type complex.'%str(e)
 				return e
 			elif t == 'real':
-				try: assert isinstance(e, REAL_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type real.'%str(e)
+				if not isinstance(e, REAL_TYPES):
+					raise Exception, 'Expression "%s" is invalid for type real.'%str(e)
 				return e
 			elif t == 'int':
-				try: assert isinstance(e, INT_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type integer.'%str(e)
+				if not isinstance(e, INT_TYPES):
+					raise Exception, 'Expression "%s" is invalid for type integer.'%str(e)
 				return e
 			elif t == 'hex': return hex(e)
 			elif t == 'bool':
-				try: assert isinstance(e, bool)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type bool.'%str(e)
+				if not isinstance(e, bool):
+					raise Exception, 'Expression "%s" is invalid for type bool.'%str(e)
 				return e
 			else: raise TypeError, 'Type "%s" not handled'%t
 		#########################
@@ -295,25 +293,22 @@ class Param(_Param, _GUIParam):
 				if not isinstance(e, VECTOR_TYPES):
 					self._lisitify_flag = True
 					e = [e]
-				try:
-					for ei in e: assert isinstance(ei, COMPLEX_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type complex vector.'%str(e)
+				if not all([isinstance(ei, COMPLEX_TYPES) for ei in e]):
+					raise Exception, 'Expression "%s" is invalid for type complex vector.'%str(e)
 				return e
 			elif t == 'real_vector':
 				if not isinstance(e, VECTOR_TYPES):
 					self._lisitify_flag = True
 					e = [e]
-				try:
-					for ei in e: assert isinstance(ei, REAL_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type real vector.'%str(e)
+				if not all([isinstance(ei, REAL_TYPES) for ei in e]):
+					raise Exception, 'Expression "%s" is invalid for type real vector.'%str(e)
 				return e
 			elif t == 'int_vector':
 				if not isinstance(e, VECTOR_TYPES):
 					self._lisitify_flag = True
 					e = [e]
-				try:
-					for ei in e: assert isinstance(ei, INT_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type integer vector.'%str(e)
+				if not all([isinstance(ei, INT_TYPES) for ei in e]):
+					raise Exception, 'Expression "%s" is invalid for type integer vector.'%str(e)
 				return e
 		#########################
 		# String Types
@@ -327,13 +322,13 @@ class Param(_Param, _GUIParam):
 		#########################
 		elif t == 'id':
 			#can python use this as a variable?
-			try: assert _check_id_matcher.match(v)
-			except AssertionError: raise Exception, 'ID "%s" must begin with a letter and may contain letters, numbers, and underscores.'%v
+			if not _check_id_matcher.match(v):
+				raise Exception, 'ID "%s" must begin with a letter and may contain letters, numbers, and underscores.'%v
 			ids = [param.get_value() for param in self.get_all_params(t)]
-			try: assert ids.count(v) <= 1 #id should only appear once, or zero times if block is disabled
-			except: raise Exception, 'ID "%s" is not unique.'%v
-			try: assert v not in ID_BLACKLIST
-			except: raise Exception, 'ID "%s" is blacklisted.'%v
+			if ids.count(v) > 1: #id should only appear once, or zero times if block is disabled
+				raise Exception, 'ID "%s" is not unique.'%v
+			if v in ID_BLACKLIST:
+				raise Exception, 'ID "%s" is blacklisted.'%v
 			return v
 		#########################
 		# Stream ID Type
@@ -346,12 +341,12 @@ class Param(_Param, _GUIParam):
 			)]
 			#check that the virtual sink's stream id is unique
 			if self.get_parent().is_virtual_sink():
-				try: assert ids.count(v) <= 1 #id should only appear once, or zero times if block is disabled
-				except: raise Exception, 'Stream ID "%s" is not unique.'%v
+				if ids.count(v) > 1: #id should only appear once, or zero times if block is disabled
+					raise Exception, 'Stream ID "%s" is not unique.'%v
 			#check that the virtual source's steam id is found
 			if self.get_parent().is_virtual_source():
-				try: assert v in ids
-				except: raise Exception, 'Stream ID "%s" is not found.'%v
+				if v not in ids:
+					raise Exception, 'Stream ID "%s" is not found.'%v
 			return v
 		#########################
 		# GUI Position/Hint
@@ -382,17 +377,15 @@ class Param(_Param, _GUIParam):
 		elif t == 'grid_pos':
 			if not v: return '' #allow for empty grid pos
 			e = self.get_parent().get_parent().evaluate(v)
-			try:
-				assert isinstance(e, (list, tuple)) and len(e) == 4
-				for ei in e: assert isinstance(ei, int)
-			except AssertionError: raise Exception, 'A grid position must be a list of 4 integers.'
+			if not isinstance(e, (list, tuple)) or len(e) != 4 or not all([isinstance(ei, int) for ei in e]):
+				raise Exception, 'A grid position must be a list of 4 integers.'
 			row, col, row_span, col_span = e
 			#check row, col
-			try: assert row >= 0 and col >= 0
-			except AssertionError: raise Exception, 'Row and column must be non-negative.'
+			if row < 0 or col < 0:
+				raise Exception, 'Row and column must be non-negative.'
 			#check row span, col span
-			try: assert row_span > 0 and col_span > 0
-			except AssertionError: raise Exception, 'Row and column span must be greater than zero.'
+			if row_span <= 0 or col_span <= 0:
+				raise Exception, 'Row and column span must be greater than zero.'
 			#get hostage cell parent
 			try: my_parent = self.get_parent().get_param('notebook').evaluate()
 			except: my_parent = ''
@@ -421,8 +414,8 @@ class Param(_Param, _GUIParam):
 			try: notebook_block = filter(lambda b: b.get_id() == notebook_id, notebook_blocks)[0]
 			except: raise Exception, 'Notebook id "%s" is not an existing notebook id.'%notebook_id
 			#check that page index exists
-			try: assert int(page_index) in range(len(notebook_block.get_param('labels').evaluate()))
-			except: raise Exception, 'Page index "%s" is not a valid index number.'%page_index
+			if int(page_index) not in range(len(notebook_block.get_param('labels').evaluate())):
+				raise Exception, 'Page index "%s" is not a valid index number.'%page_index
 			return notebook_id, page_index
 		#########################
 		# Import Type
diff --git a/grc/python/Platform.py b/grc/python/Platform.py
index ec3f94096..a9c2b18ad 100644
--- a/grc/python/Platform.py
+++ b/grc/python/Platform.py
@@ -1,5 +1,5 @@
-"""
-Copyright 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
+__doc__ = """
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
diff --git a/grc/python/Port.py b/grc/python/Port.py
index 6e5a5c59f..3846b0f4e 100644
--- a/grc/python/Port.py
+++ b/grc/python/Port.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -83,16 +83,16 @@ class Port(_Port, _GUIPort):
 
 	def validate(self):
 		_Port.validate(self)
-		try: assert self.get_enabled_connections() or self.get_optional()
-		except AssertionError: self.add_error_message('Port is not connected.')
-		try: assert self.is_source() or len(self.get_enabled_connections()) <= 1
-		except AssertionError: self.add_error_message('Port has too many connections.')
+		if not self.get_enabled_connections() and not self.get_optional():
+			self.add_error_message('Port is not connected.')
+		if not self.is_source() and len(self.get_enabled_connections()) > 1:
+			self.add_error_message('Port has too many connections.')
 		#message port logic
 		if self.get_type() == 'msg':
-			try: assert not self.get_nports()
-			except AssertionError: self.add_error_message('A port of type "msg" cannot have "nports" set.')
-			try: assert self.get_vlen() == 1
-			except AssertionError: self.add_error_message('A port of type "msg" must have a "vlen" of 1.')
+			if self.get_nports():
+				self.add_error_message('A port of type "msg" cannot have "nports" set.')
+			if self.get_vlen() != 1:
+				self.add_error_message('A port of type "msg" must have a "vlen" of 1.')
 
 	def rewrite(self):
 		"""
@@ -134,8 +134,7 @@ class Port(_Port, _GUIPort):
 		if not nports: return ''
 		try:
 			nports = int(self.get_parent().get_parent().evaluate(nports))
-			assert 0 < nports
-			return nports
+			if 0 < nports: return nports
 		except: return 1
 
 	def get_optional(self): return bool(self._optional)
diff --git a/grc/python/expr_utils.py b/grc/python/expr_utils.py
index 3c39f5d89..a2e56eedf 100644
--- a/grc/python/expr_utils.py
+++ b/grc/python/expr_utils.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -118,7 +118,7 @@ def sort_variables(exprs):
 	Get a list of variables in order of dependencies.
 	@param exprs a mapping of variable name to expression
 	@return a list of variable names
-	@throws AssertionError circular dependencies
+	@throws Exception circular dependencies
 	"""
 	var_graph = get_graph(exprs)
 	sorted_vars = list()
@@ -126,7 +126,7 @@ def sort_variables(exprs):
 	while var_graph.get_nodes():
 		#get a list of nodes with no edges
 		indep_vars = filter(lambda var: not var_graph.get_edges(var), var_graph.get_nodes())
-		assert indep_vars
+		if not indep_vars: raise Exception('circular dependency caught in sort_variables')
 		#add the indep vars to the end of the list
 		sorted_vars.extend(sorted(indep_vars))
 		#remove each edge-less node from the graph
diff --git a/grc/python/extract_docs.py b/grc/python/extract_docs.py
index f41f415b2..aa85397f9 100644
--- a/grc/python/extract_docs.py
+++ b/grc/python/extract_docs.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -81,8 +81,8 @@ def extract(key):
 	@param key the block key
 	@return a string with documentation
 	"""
-	try: assert _docs_cache.has_key(key)
-	except: _docs_cache[key] = _extract(key)
+	if not _docs_cache.has_key(key):
+		_docs_cache[key] = _extract(key)
 	return _docs_cache[key]
 
 if __name__ == '__main__':