DartBot
commented
9 years ago 
Siggi, could you take a first crack at defining what our policy and reasoning are?
Set owner to @sigmundch. Added Library-Polymer, Docs-API, Docs-Tutorials labels.
Closed DartBot closed 9 years ago
DartBot
commented
9 years ago
Siggi, could you take a first crack at defining what our policy and reasoning are?
Set owner to @sigmundch. Added Library-Polymer, Docs-API, Docs-Tutorials labels.
DartBot
commented
9 years ago This comment was originally written by yu.asaku...@gmail.com
Also related: issue dart-lang/sdk#15229.
DartBot
commented
9 years ago 
These are great points, @yu.asakusa thanks for filing this bug.
I'm cc'ing a few others to confirm.
Because of today's timing of Dart script tags in Dartium (Dartium launches code at dom-content-loaded), we should state our policy like we did in the 'embedding-in-html' article: put it at the end to keep the behavior consistent after compiling with dart2js. And, as you suggest, the examples should be modified to put the script tag at the end.
We have design ideas to eventually support sync execution of Dart script tags, but it's not going to be available for a while. When we reach that point we'll probably revisit the policy.
cc @jmesserly. cc @blois. cc @vsmenon.
DartBot
commented
9 years ago 
To best approximate Dartium behavior, the dart2js script should have a defer attribute. If you do this, then it can be anywhere in the file (head included).
Related is https://code.google.com/p/dart/issues/detail?id=15229.
DartBot
commented
9 years ago 
Pete, good point. Our skeleton app from Dart Editor should add defer. I've CC'ed Keerti.
cc @keertip.
DartBot
commented
9 years ago DartBot
commented
9 years ago DartBot
commented
9 years ago DartBot
commented
9 years ago 
This issue has been moved to Github as part of a migration. Please use the Issue on Github going forward: https://github.com/dart-lang/dartlang.org/issues
Added MovedToGithub label.
Originally opened as dart-lang/sdk#15980
This issue was originally filed by yu.as...@gmail.com
URL (if available): Some of https://www.dartlang.org/polymer-dart/ https://www.dartlang.org/docs/tutorials/polymer-intro/ https://api.dartlang.org/docs/channels/stable/latest/polymer.html
Issue/feedback: The first example on <https://www.dartlang.org/polymer-dart/> places <script> elements in <head>. The same holds for the sample code on <https://www.dartlang.org/docs/tutorials/polymer-intro/> and the the sample code generated by Dart Editor when the user selects “Web application (using the polymer library)”.
I assume that there is a reason the sample codes using Polymer.dart tend to place <script> tags on top, such as to avoid the flash of unstyled content in some cases. However, this means that the Dart code and the compiled JavaScript code are executed at different timing. I was not the only one who was confused by this discrepancy (see issue dart-lang/sdk#15125).
I think that the reason for putting <script> elements on top (assuming there is a reason) and implication of doing so (Dart and JavaScript behave differently) should be stated somewhere in the documentation of Polymer.dart.
(Needless to say, if there is no reason to put <script> elements on top, then the codes should be modified. Note that the page “Embedding Dart in HTML” <https://www.dartlang.org/articles/embedding-in-html/#dart-html-semantics> recommends to place <script> elements at the end of a document, seemingly to avoid this very discrepancy.)