It takes 2 parameters, the first being a tiddler object, the second being the name of the attribute or field to be accessed (a string).

Soon this should also support access to slices, which is achieved by preceding the second parameter string with ## or :: as appropriate.
For example
store.getValue(tiddler, "##foo")
should return the value of the section foo.
bag
tiddlywikidev_public
created
Wed, 09 Mar 2011 11:24:04 GMT
creator
jon
modified
Wed, 09 Mar 2011 11:24:04 GMT
modifier
jon
tags
method
store
theme
TWDocTheme