Whitespace is any non-empty string containing only characters that have the Pattern_White_Space Unicode property, namely:
U+0009 (horizontal tab, '\t')U+000A (line feed, '\n')U+000B (vertical tab)U+000C (form feed)U+000D (carriage return, '\r')U+0020 (space, ' ')U+0085 (next line)U+200E (left-to-right mark)U+200F (right-to-left mark)U+2028 (line separator)U+2029 (paragraph separator)Rust is a "free-form" language, meaning that all forms of whitespace serve only to separate tokens in the grammar, and have no semantic significance.
A Rust program has identical meaning if each whitespace element is replaced with any other legal whitespace element, such as a single space character.
© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/reference/whitespace.html