Allow to give name and dtype when doing scalar constant.

theano/scalar/basic.py

@@ -277,10 +277,10 @@ def convert(x, dtype=None):
     return x_
 
 
-def constant(x):
-    x = convert(x)
+def constant(x, name=None, dtype=None):
+    x = convert(x, dtype=dtype)
     assert x.ndim == 0
-    return ScalarConstant(get_scalar_type(str(x.dtype)), x)
+    return ScalarConstant(get_scalar_type(str(x.dtype)), x, name=name)
 
 
 class Scalar(Type):

theano/scalar/tests/test_basic.py

@@ -488,5 +488,14 @@ def test_grad_abs():
 # in test_fusion, TestCompositeCodegen
 
 
+def test_constant():
+    c = constant(2, name='a')
+    assert c.name == 'a'
+    assert c.dtype == 'int8'
+    c = constant(2, dtype='float32')
+    assert c.name is None
+    assert c.dtype == 'float32'
+
+
 if __name__ == '__main__':
     unittest.main()