Dart backend: support for __getslice__, ** (Math.pow), // (Math.floor…

…), updated nbody_fast.html so it also works with Dart.

pythonjs/python_to_pythonjs.py

@@ -1148,7 +1148,9 @@ def visit_Subscript(self, node):
 			)
 
 	def visit_Slice(self, node):
-		if self._with_js:
+		if self._with_dart:
+			lower = upper = step = 'null'
+		elif self._with_js:
 			lower = upper = step = 'undefined'
 		else:
 			lower = upper = step = None
@@ -1310,7 +1312,7 @@ def _visit_assign_helper(self, node, target):
 					writer.write('%s = %s' % (self.visit(target), node_value))
 
 			elif self._with_dart and writer.is_at_global_level():
-				writer.write('var %s = %s' % (self.visit(target), node_value))
+				writer.write('JS("var %s = %s")' % (self.visit(target), node_value))
 			else:
 				writer.write('%s = %s' % (self.visit(target), node_value))
 
@@ -1723,15 +1725,34 @@ def visit_FunctionDef(self, node):
 			else:
 				decorators.append( decorator )
 
-		if self._with_js or javascript or self._with_dart:
+		if self._with_dart:
+			if node.args.vararg:
+				raise SyntaxError( 'pure javascript functions can not take variable arguments (*args)' )
+			elif node.args.kwarg:
+				raise SyntaxError( 'pure javascript functions can not take variable keyword arguments (**kwargs)' )
+
+			for dec in with_dart_decorators: writer.write('@%s'%dec)
+
+			args = []
+			offset = len(node.args.args) - len(node.args.defaults)
+			for i, arg in enumerate(node.args.args):
+				a = arg.id
+				dindex = i - offset
+				if dindex >= 0 and node.args.defaults:
+					default_value = self.visit( node.args.defaults[dindex] )
+					args.append( '%s=%s' %(a, default_value) )
+				else:
+					args.append( a )
+
+			writer.write( 'def %s( %s ):' % (node.name, ','.join(args)) )
+
+
+		elif self._with_js or javascript:
 			if node.args.vararg:
 				raise SyntaxError( 'pure javascript functions can not take variable arguments (*args)' )
 			elif node.args.kwarg:
 				raise SyntaxError( 'pure javascript functions can not take variable keyword arguments (**kwargs)' )
 
-			if self._with_dart:
-				for dec in with_dart_decorators:
-					writer.write('@%s'%dec)
 			args = [ a.id for a in node.args.args ]
 			writer.write( 'def %s( %s ):' % (node.name, ','.join(args)) )
 
@@ -1748,7 +1769,11 @@ def visit_FunctionDef(self, node):
 				a = ','.join( local_vars-global_vars )
 				writer.write('var(%s)' %a)
 
-		if self._with_js or javascript or self._with_dart:
+		#####################################################################
+		if self._with_dart:
+			pass
+
+		elif self._with_js or javascript:
 			if node.args.defaults:
 				offset = len(node.args.args) - len(node.args.defaults)
 				for i, arg in enumerate(node.args.args):

pythonjs/pythonjs.py

@@ -255,7 +255,13 @@ def visit_Call(self, node):
 			return s
 
 		elif name == 'dart_import':
-			return 'import "%s";' %node.args[0].s
+			if len(node.args) == 1:
+				return 'import "%s";' %node.args[0].s
+			elif len(node.args) == 2:
+				return 'import "%s" as %s;' %(node.args[0].s, node.args[1].s)
+			else:
+				raise SyntaxError
+
 
 		else:
 			if node.args:
@@ -467,7 +473,7 @@ def visit_For(self, node):
 
 		out = []
 		out.append( self.indent() + 'var %s = %s;' % (iname, iter) )
-		out.append( self.indent() + 'var %s = 0;' % index )
+		#out.append( self.indent() + 'var %s = 0;' % index )
 
 		self._visit_for_prep_iter_helper(node, out, iname)
 

pythonjs/pythonjs_to_dart.py

@@ -206,14 +206,19 @@ def visit_ClassDef(self, node):
 
 	def _visit_for_prep_iter_helper(self, node, out, iter_name):
 		out.append(
-			self.indent() + 'if (%s is dict) { %s = %s.keys(); }' %(iter_name, iter_name, iter_name)
+			#self.indent() + 'if (%s is dict) { %s = %s.keys(); }' %(iter_name, iter_name, iter_name)
+			self.indent() + 'if (%s is dict) %s = %s.keys();' %(iter_name, iter_name, iter_name)
 		)
 
 
 	def visit_Expr(self, node):
-		# XXX: this is UGLY
 		s = self.visit(node.value)
-		if not s.endswith(';'):
+		if isinstance(node.value, ast.Call) and isinstance(node.value.func, ast.Name) and node.value.func.id == 'JS':
+			if s.endswith('}') and 'return' in s.split(' '):
+				pass
+			elif not s.endswith(';'):
+				s += ';'
+		elif not s.endswith(';'):
 			s += ';'
 		return s
 
@@ -253,7 +258,21 @@ def _visit_function(self, node):
 			else:
 				raise SyntaxError
 
-		args = self.visit(node.args)
+		args = []  #self.visit(node.args)
+		oargs = []
+		offset = len(node.args.args) - len(node.args.defaults)
+		for i, arg in enumerate(node.args.args):
+			a = arg.id
+			dindex = i - offset
+			if dindex >= 0 and node.args.defaults:
+				default_value = self.visit( node.args.defaults[dindex] )
+				oargs.append( '%s=%s' %(a, default_value) )
+			else:
+				args.append( a )
+
+		if oargs:
+			args.append( '[%s]' % ','.join(oargs) )
+
 		buffer = self.indent()
 		if hasattr(node,'_prefix'): buffer += node._prefix + ' '
 

runtime/dart_builtins.py

@@ -3,6 +3,7 @@
 # License: "New BSD"
 
 dart_import('dart:collection')
+dart_import('dart:math', 'Math')
 
 @dart.extends
 class list( ListBase ):
@@ -31,6 +32,13 @@ def __getitem__(self, index):
 	def __setitem__(self, index, value):
 		self[...][index] = value
 
+	def __getslice__(self, start, stop, step):
+		if stop == null and step == null:
+			return self[...].sublist( start )
+		elif stop < 0:
+			stop = self[...].length + stop
+			return self[...].sublist(start, stop)
+
 	def append(self, item):
 		self[...].add( item )
 
@@ -39,7 +47,7 @@ def index(self, obj):
 
 
 #@dart.extends
-class dict( HashMap ):
+class dict: #( HashMap ):
 	'''
 	HashMap can not be extended anymore:
 		https://groups.google.com/a/dartlang.org/forum/#!msg/announce/Sj3guf3es24/YsPCdT_vb2gJ
@@ -77,3 +85,5 @@ def range(n):
 		i += 1
 	return r
 
+def len(a):
+	return a.length

tests/nbody_fast.html

@@ -62,15 +62,10 @@
 				 5.15138902046611451e-05 * SOLAR_MASS) }
 
 
-SYSTEM = []
-for key in BODIES:
-	print key
-	SYSTEM.append( BODIES[key] )
 
-PAIRS = combinations(SYSTEM)
 
 
-def advance(dt, n, bodies=SYSTEM, pairs=PAIRS):
+def advance(dt, n, bodies, pairs):
 	for i in xrange(n):
 		for pair in pairs:
 			p1,p2 = pair
@@ -99,7 +94,7 @@
 			r[2] += dt * v[2]
 
 
-def report_energy(bodies=SYSTEM, pairs=PAIRS, e=0.0):
+def report_energy(bodies, pairs, e=0.0):
 	for pair in pairs:
 		p1,p2 = pair
 		vec1, v1, m1 = p1
@@ -119,7 +114,7 @@
 	return e
 
 
-def offset_momentum(ref, bodies=SYSTEM, px=0.0, py=0.0, pz=0.0):
+def offset_momentum(ref, bodies, px=0.0, py=0.0, pz=0.0):
 	for w in bodies:
 		r, v, m = w
 		vx, vy, vz = v
@@ -134,24 +129,28 @@
 
 
 def test_nbody(iterations):
+	SYSTEM = []
+	for key in BODIES: SYSTEM.append( BODIES[key] )
+	PAIRS = combinations(SYSTEM)
+
 	# Warm-up runs.
-	report_energy()
-	advance(0.01, 20000)
-	report_energy()
+	report_energy( SYSTEM, PAIRS )
+	advance(0.01, 20000,  SYSTEM, PAIRS )
+	report_energy( SYSTEM, PAIRS )
 
 	times = []
 	for _ in xrange(iterations):
 		t0 = time()
-		report_energy()
-		advance(0.01, 20000)
-		report_energy()
+		report_energy( SYSTEM, PAIRS )
+		advance(0.01, 20000, SYSTEM, PAIRS)
+		report_energy( SYSTEM, PAIRS )
 		t1 = time()
 		times.append(t1 - t0)
 	return times
 
 
 
-def test():
+def main():
 	times = test_nbody( 3 )
 	for t in times:
 		print 'time', t
@@ -161,6 +160,6 @@
 
 </head>
 <body>
-<button id="mybutton" onclick="test()">click me</button>
+<button id="mybutton" onclick="main()">click me</button>
 </body>
 </html>

tests/server.py

@@ -28,6 +28,7 @@
 	runtime_dart = os.path.abspath('../runtime/dart_builtins.py'),
 
 	dart2js = os.path.expanduser( '~/dart/dart-sdk/bin/dart2js'),
+	dartanalyzer = os.path.expanduser( '~/dart/dart-sdk/bin/dartanalyzer'),
 
 )
 
@@ -62,14 +63,18 @@ def pythonjs_to_dart(src):
 		stdin = subprocess.PIPE,
 		stdout = subprocess.PIPE
 	)
+	dart_input = '/tmp/dart2js-input.dart'
 	stdout, stderr = p.communicate( src.encode('utf-8') )
-	open( '/tmp/dart2js-input.js', 'wb').write( stdout )
+	open( dart_input, 'wb').write( stdout )
+	ecode = subprocess.call( [PATHS['dartanalyzer'], dart_input] )
+	if ecode == 2:
+		raise SyntaxError
 
 	cmd = [
 		PATHS['dart2js'],
 		#'-c', ## insert runtime checks
 		'-o', '/tmp/dart2js-output.js',
-		'/tmp/dart2js-input.js'
+		dart_input
 	]
 	subprocess.call( cmd )
 	return open('/tmp/dart2js-output.js', 'rb').read().decode('utf-8')

tests/test_for_loop.html

@@ -4,8 +4,10 @@
 
 <script type="text/python">
 
-
 def main():
+	'''
+	basic for loop tests
+	'''
 
 	a = [1,2,3]
 	for x in a: