Groovy
Retrieve the first object (index [0]) among all objects attached to this page and class XWikiComments
com.xpn.xwiki.api.Object@70b72a40
Retrieve all objects attached to this page and of class XWikiComments
[com.xpn.xwiki.api.Object@715f0914, com.xpn.xwiki.api.Object@164d3a32, com.xpn.xwiki.api.Object@2827b40e, com.xpn.xwiki.api.Object@469e17ba, com.xpn.xwiki.api.Object@3527d88e, com.xpn.xwiki.api.Object@4afa6de5, com.xpn.xwiki.api.Object@7f44fbd7, com.xpn.xwiki.api.Object@9f22188, com.xpn.xwiki.api.Object@77776cd1]
Retrieve all objects attached to this page and of class XWikiComments and one of their properties
objsAuthors = doc.getObjects('XWiki.XWikiComments').author
objsAuthor = doc.getObjects('XWiki.XWikiComments')[2].author
println objs[0].author
println objsAuthors
println objsAuthor