pub fn requires_space(&self) -> bool {
        use super::tokenizer::Token::*;
        match *self {
            TOpenParen | TCloseParen | TOpenBracket | TCloseBracket | TOpenBrace | TCloseBrace
            | TComma | TPlus | TMinus | TTimes | TDivide | TModulo | TEqual | TBar | TAtMark
            | TDot | TColon | TSemicolon | TQuestion | TBang | TEqualEqual | TNotEqual
            | TLessThanOrEqual | TGreaterThanOrEqual | TLessThan | TGreaterThan | TLogicalAnd
            | TLogicalOr | TBitwiseAnd | TXor | TMax | TMin | TPow | TEndOfInput => false,
            _ => true,
        }
    }
Returns whether this token requires a space preceding it when printing a
token stream.
weld/src/syntax/tokenizer.rs