title: How to use proguard.config setting in project.properties file?
body: <p>I use eclipse and I guess ant building system. In my project root i have a project.properties file which contains proguard.config setting. This setting is said in sdk examples to either</p>
  
  <blockquote>
    <p>proguard.config=${sdk.dir}/tools/proguard/proguard-android.txt:proguard-project.txt</p>
  </blockquote>
  
  <p>or</p>
  
  <blockquote>
    <p>proguard.config=${sdk.dir}/tools/proguard/proguard-android-optimize.txt:proguard-project.txt</p>
  </blockquote>
  
  <p>I have found somewhere that you can state multiple files delimited by colon ":".</p>
  
  <p>But nowhere it is explained in depth which of files takes precedence. I mean does this use file proguard-android.txt from {sdk.dir} folder or proguard-project.txt from project root folder or does it somehow merge the setting from the two.
  What is the correct usage? Should I reference both files: the one in {sdk.dir} folder as a default and my proguard-project.txt for project specific stuff? Or should I take proguard-android.txt or proguard-android-optimize.txt and use that as a base for my proguard-project.txt and modify accordingly?
  Basically, what is the correct usage or best practice? Experimenting and testing is a bit time consuming to say the least.</p>