This works similarly to the {thread/frame/process/target.script:...} feature - you write a summary string, part of which is
${var.script:someFuncName}
someFuncName is expected to be declared as
def someFuncName(SBValue,otherArgument) - essentially the same as a summary function
Since . -> [] are the only allowed separators, and % is used for custom formatting, .script: would not be a legitimate symbol anyway, which makes this non-ambiguous
llvm-svn: 220821