[pkg:polymer] add support for bool/int/double/String attributes

add support for bool/int/double/String attributes

BUG=

[Jennifer Messerly, 2013-08-06 16:26:55]

Needs a test. Maybe we can port from polymer.js?

[Jennifer Messerly, 2013-08-06 16:31:17]

update title. String works too :)

[Siggi Cherem (dart-lang), 2013-08-06 16:40:39]

lgtm

https://chromiumcodereview.appspot.com/22417004/diff/1/lib/polymer_element.dart
File lib/polymer_element.dart (right):

https://chromiumcodereview.appspot.com/22417004/diff/1/lib/polymer_element.da...
lib/polymer_element.dart:130: propObserver.value = int.parse(value, onError: (x)
=> null);
should we assign onError or just skip setting the property altogether?

https://chromiumcodereview.appspot.com/22417004/diff/1/lib/polymer_element.da...
lib/polymer_element.dart:135: propObserver.value = value;
how about:
propObserver.value = value.toString();
?

[Jennifer Messerly, 2013-08-06 16:44:23]

https://chromiumcodereview.appspot.com/22417004/diff/1/lib/polymer_element.dart
File lib/polymer_element.dart (right):

https://chromiumcodereview.appspot.com/22417004/diff/1/lib/polymer_element.da...
lib/polymer_element.dart:130: propObserver.value = int.parse(value, onError: (x)
=> null);
On 2013/08/06 16:40:39, Siggi Cherem (dart-lang) wrote:
> should we assign onError or just skip setting the property altogether?

good question. I figured setting to "null" would signal an invalid value. But
not setting is consistent with some of the error-tolerant HTML behavior. I'll
need to do more research on this

https://chromiumcodereview.appspot.com/22417004/diff/1/lib/polymer_element.da...
lib/polymer_element.dart:135: propObserver.value = value;
On 2013/08/06 16:40:39, Siggi Cherem (dart-lang) wrote:
> how about:
> propObserver.value = value.toString();
> ?

value will always be a string because it comes from attributes:
http://api.dartlang.org/docs/releases/latest/dart_html/Element.html#attributes

[Siggi Cherem (dart-lang), 2013-08-06 16:46:00]

https://chromiumcodereview.appspot.com/22417004/diff/1/lib/polymer_element.dart
File lib/polymer_element.dart (right):

https://chromiumcodereview.appspot.com/22417004/diff/1/lib/polymer_element.da...
lib/polymer_element.dart:135: propObserver.value = value;
On 2013/08/06 16:44:23, John Messerly wrote:
> On 2013/08/06 16:40:39, Siggi Cherem (dart-lang) wrote:
> > how about:
> > propObserver.value = value.toString();
> > ?
> 
> value will always be a string because it comes from attributes:
> http://api.dartlang.org/docs/releases/latest/dart_html/Element.html#attributes

Ah, <facepalm>, makes sense. thx

[Jennifer Messerly, 2013-08-06 20:04:52]

https://chromiumcodereview.appspot.com/22417004/diff/1/lib/polymer_element.dart
File lib/polymer_element.dart (right):

https://chromiumcodereview.appspot.com/22417004/diff/1/lib/polymer_element.da...
lib/polymer_element.dart:130: propObserver.value = int.parse(value, onError: (x)
=> null);
On 2013/08/06 16:44:23, John Messerly wrote:
> On 2013/08/06 16:40:39, Siggi Cherem (dart-lang) wrote:
> > should we assign onError or just skip setting the property altogether?
> 
> good question. I figured setting to "null" would signal an invalid value. But
> not setting is consistent with some of the error-tolerant HTML behavior. I'll
> need to do more research on this


hmm, Polymer source code is not helpful in this case. If they fail to parse,
they let it become a string:

https://github.com/Polymer/polymer/blob/master/src/lib/deserialize.js#L24

that would most likely cause a checked mode error in Dart, which would leave the
original value.

input type=number will give you a NaN if "value" attribute is invalid, but
that's also the default.

based on that, I'm inclined to switch it to your suggestion of preserving the
original value.

[Jennifer Messerly, 2013-10-03 20:52:51]

closing this, it was superseded by https://codereview.chromium.org/24149003/