Multiline strings have one more escape, unique to them: a backslash at the end of a line. Today you implement that trim, which lets a long value be written across neat lines while parsing to a single unbroken string.
Trim the newline and following whitespace after a line-ending backslash.
Multiline basic strings add one escape the single-line form does not have: a
backslash at the end of a line. When a \ is the last non-whitespace character
on a line, TOML removes the backslash, the newline after it, and all leading
whitespace of the next line - including further blank lines - until it reaches the
next non-whitespace character. This lets a writer break a long value across tidy,
indented lines while the parsed value has no line breaks at all.
So a string whose content is \ then a newline then The quick then \ then a
newline then brown fox folds down to The quick brown fox: each trailing
backslash swallows the newline and the indentation that follows. The distinction to
respect is placement - a backslash followed by a real character (\n, \t) is an
ordinary escape from the previous lessons, while a backslash followed only by
whitespace-then-newline is this line-continuation trim. This is the classic edge the
TOML spec calls out, and pinning it makes long embedded text behave.
// inside a multiline basic string, when a '\' is followed only by// whitespace to the end of the line:// drop the backslash, the newline, and ALL leading whitespace// (spaces, tabs, newlines) of the following line(s)// a '\' followed by a real character is an ordinary escape