diffUtil::fullFunctionality
returns 1 if all is supported

diffUtil::diffFiles ?flags? file1 file2
-nocase -i -b -w
-align list
-range list

returns a list of {line1 size1 line2 size2}
lines are numbered from 1..

diffUtil::diffLists ?flags? list1 list2
like diffFiles, but with lines in lists
numbers in result are indexes i.e 0..

diffUtil::diffStrings ?flags? line1 line2
-nocase -i -b -w -words

returns a list of substrings from alternating lines
str1sub1 str2sub1 str1sub2 str2sub2...
str1sub* concatenated gives line1
str2sub* concatenated gives line2
str1subN and str2subN are equal when N is odd

diffUtil::matchBlocks ?flags? lines1 lines2
returns like diffLists
