[optimize]: remove the return value option

[fansehep]

shaun-rs/src/parser/mod.rs

Lines 1226 to 1231 in 7974f22

	fn parse_expression(&mut self, precedence: Precedence) -> Result<Option<Expression>> {
	if !is_prefix_oper(&self.pre_token) {
	return Err(Error::ParseErr(fmt_err!(
	"No prefixOperatorFunc for: {:?}",
	&self.pre_token
	)));

Now in parse_expression function, it's return value type is Result<Option<Expression>>, but in fact, we will not return None, So use Option is redundant.

remove the Option, and change other place which use this function.

[apengn]

Can you assign it to me?

[fansehep]

Can you assign it to me?

sure！Really thanks for you. ❤️