A useful diff removes the differences you do not care about and keeps the ones you do. Precision controls how a changed line is highlighted; ignore rules control which differences count at all.
01Choosing precision
Start with a smart mode that chooses word precision when the changed pair shares a meaningful token and character precision otherwise.
Use word precision when whole identifiers or words changed.
Use character precision for small edits inside a long token, such as a changed digit.
02Ignore rules
Whitespace, case, and line-ending rules make those differences compare equal.
A literal or regular-expression rule removes a matching pattern, such as a timestamp or build id, from the comparison key.
Rules apply to the comparison key only; the retained text and any exported file are never rewritten.
Frequently asked questions
Do ignore rules modify my files?
No. They change only which differences are matched; the editors and every exported file keep the bytes you supplied.
When should I use character precision instead of word precision?
Use character precision for a small edit inside one long token, such as a changed digit or letter, where word-level highlighting would mark the whole token.
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