title: Grails compiler keeps running again and again, possibly because of syntax error
body: <p>I got this problem several times: Sometimes when I command : grails run-app, the compiler just running again and again, even though I change nothing after that. It looks like:</p>
  
  <pre><code>Running Grails application..
  Server running. Browse to http://localhost:8080/LiningTest
    [groovyc] Compiling 1 source file to E:\workspace\W1\LiningTest\target\classes
  
    [groovyc] Compiling 2 source files to E:\workspace\W1\LiningTest\target\classe
  s
     [delete] Deleting directory C:\Documents and Settings\Long\.grails\1.3.6\proj
  ects\LiningTest\tomcat
  Running Grails application..
  Server running. Browse to http://localhost:8080/LiningTest
    [groovyc] Compiling 1 source file to E:\workspace\W1\LiningTest\target\classes
  
    [groovyc] Compiling 2 source files to E:\workspace\W1\LiningTest\target\classe
  s
     [delete] Deleting directory C:\Documents and Settings\Long\.grails\1.3.6\proj
  ects\LiningTest\tomcat
  Running Grails application..
  Server running. Browse to http://localhost:8080/LiningTest
    [groovyc] Compiling 1 source file to E:\workspace\W1\LiningTest\target\classes
  ...
  </code></pre>
  
  <p>The compiler succeeded when "Server running", but then it automatically re-compile some files (I don't know which file), and run again, and then recompile again...</p>
  
  <p>I have met this problem once when I have a syntax error</p>
  
  <pre><code>constraint {
  number(min:0.50) // the right way is "min: 0..50"
  }
  </code></pre>
  
  <p>The question is why this problem happened, and how I can find the cause of the problem. (I guess that I miss some comma/dot somewhere, but now it's hard to find, because of there's no error message!)</p>
  
  <p><strong>UPDATE</strong>: Now I see the problem is that I don't follow the folder structure rules when placing non-domain class in src/groovy.</p>