• Related to let's add --oneline option to the rewrite command #580

I've implemented the single-line option that prints a single expression on a single line. This option relies on the single option. Hence, the name is single-line, and not one-line as suggested originally.

Another reason is that ChatGPT thinks "single line" is used more commonly:

The correct expression is "on a single line."

When referring to text or code being written or displayed in one continuous row without line breaks, the phrase "on a single line" is the most common and accurate usage. For example, you would say, "Please print the output on a single line."

"In one line" is less commonly used, but it could still be understood in certain contexts. However, "on a single line" is the more conventional choice.