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src/site/docs/tutorials/connect-dart-html/errors-warnings.markdown

----
-layout: default
-title: "What Is Dart Editor Trying to Tell Me?"
-description: "Errors and warnings and code completions"
-has-permalinks: true
-tutorial:
-  id: errors-warnings
----
-
-{% capture back_to %}
-<a href="index.html" style="font-size: 9pt">2: Connect Dart &amp; HTML</a>
-{% endcapture %}
-
-{% capture whats_the_point %}
-
-* Dart Editor reports errors and warnings.
-* Errors are either run-time or compile-time.
-* Warnings are hints that your code might not work.
-
-{% endcapture %}
-
-{% capture content %}
-
-As you type, Dart Editor processes the text,
-analyzing it for errors and performing code completion.
-The sections below show you a few of the errors and
-warnings you might see.
-They also show you how to use Dart Editor's code completion help.
-
-Follow along with the instructions as you transform
-the code for the default helloworld command-line app into this code:
-
-{% prettify dart %}
-import 'dart:html';
-void main() {
-  query('#RipVanWinkle').text = 'Wake up, sleepy head!';
-}
-{% endprettify %}
-
-##Errors
-Place the text cursor before the 'v' in void,
-and begin typing the first line of code,
-the `import` directive,
-and stop just after you type the first quotation mark.
-
-<img src="images/error-editor-screenshot.png"
-     alt="Dart Editor error">
-
-You will see a small red 'x'
-in the gutter on the left side of the **Editor pane**.
-This means that Dart Editor has detected an error.
-When you point to the red 'x',
-a tooltip displays a helpful error message.
-
-<img src="images/error-tooltip-screenshot.png"
-     alt="Dart Editor error tooltip">
-
-This particular error is syntactic.
-The single quote starts a string literal,
-which is left uncompleted.
-Errors can be either compile-time or run-time.
-Compile-time errors prevent your program from running at all.
-Run-time errors result in exceptions.
-
-Finish typing the complete line of code including the semi-colon (;)
-and the red 'x' disappears.
-
-<aside class="alert" markdown="1">
-**Tip:** Save your file with **File > Save**.
-In some versions of Dart Editor,
-you need to save the file and start typing again
-before a newly imported library is detected.
-</aside>
-
-##Warnings
-
-Now delete the line of code that calls print(),
-and start typing the function call to query().
-Stop after you type the first parenthesis.
-Note that Dart Editor helpfully provides a matching parenthesis.
-Note also that Dart Editor displays
-a yellow warning symbol in the gutter.
-
-<img src="images/warning-editor-screenshot.png"
-     alt="Dart Editor warning">
-
-In the background, Dart Editor does API lookup.
-Dart Editor recognizes the top-level query() function
-from the Dart HTML library,
-but it has detected a possible problem.
-Point the mouse at the yellow warning sign and 
-a helpful warning message will be displayed in a tooltip:
-
-<img src="images/warning-tooltip-screenshot.png"
-     alt="Dart Editor warning tooltip">
-
-Dart Editor is telling you that query() requires
-a string argument and you have not yet provided one.
-Warnings are hints that your code might not work,
-but they don't prevent your program from executing.
-
-##Code completion
-
-Continue typing, entering '#RipVanWinkle'
-as the argument to the query() function,
-and stop after you type the period.
-Dart Editor displays a menu with auto-complete suggestions
-based on the context.
-You can also bring up the menu by typing **Ctl+Space**.
-
-<img src="images/query-api-lookup.png"
-     alt="Lookup query in Dart libraries in Dart Editor">
-
-Scroll down and choose text, or just type it in.
-
-Finish your edits,
-and save the file with **File > Save**.
-
-<div class="row">
-  <div class="span3">
-  <a href="index.html"><i class="icon-chevron-left"> </i> Back to Target 2</a>
-  </div>
-</div>
-
-{% endcapture %}
-
-{% include tutorial-sidebar.html %}