rstrip

rstrip is a string processing operation found in several programming languages that removes characters from the right end of a string. The name stands for right-strip, referring to the direction of removal. The behavior is most commonly associated with removing trailing whitespace, but languages often allow a custom set of characters to be removed as well.

In its default form, rstrip removes trailing whitespace characters such as spaces, tabs, and newlines. When an optional argument is provided, it is interpreted as a set of characters to remove from the end of the string. The characters are considered individually; removal continues as long as the last character belongs to the specified set. The method does not affect characters at the left side or within the string, only trailing characters.

Return value and mutability vary by language. In languages with immutable strings (such as Python), rstrip returns a new string and leaves the original unchanged. Some languages offer a destructive in-place variant (often named rstrip!), which modifies the original string.

Examples illustrate common usage: "hello world ".rstrip() yields "hello world"; "path/to/file.txt\n".rstrip() yields "path/to/file.txt". When a character set is supplied, e.g., "abc123".rstrip("123"), trailing characters in the set are removed until a character not in the set is encountered, producing "abc".

See also lstrip (left-strip) and strip (both sides). Rstrip is frequently used to clean input, remove line terminators, or prepare strings for parsing and storage.