Value | Meaning |
---|---|
none'n' | Current items are equal; no editing is necessary. |
substitute's' | Substitute current item in target with current item in source. |
insert'i' | Insert current item from the source into the target. |
remove'r' | Remove current item from the target. |
Encodes edit operations necessary to transform one sequence into another. Given sequences s (source) and t (target), a sequence of EditOp encodes the steps that need to be taken to convert s into t. For example, if s = "cat" and "cars", the minimal sequence that transforms s into t is: skip two characters, replace 't' with 'r', and insert an 's'. Working with edit operations is useful in applications such as spell-checkers (to find the closest word to a given misspelled word), approximate searches, diff-style programs that compute the difference between files, efficient encoding of patches, DNA sequence analysis, and plagiarism detection.