You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: builtin.rs
    path of file: ./repos/surrealdb/core/src/syn/v2/parser
    
    the code of the file until where you have to start completion: use super::{ParseResult, Parser};
use crate::{
	sql::{Constant, Function, Ident, Value},
	syn::v2::{
		parser::{mac::expected, ParseError, ParseErrorKind},
		token::{t, Span},
	},
};
use phf::phf_map
    
	pub fn parse_builtin(&mut self, start: Span) -> ParseResult<Value> {
		let mut last_span = start;
		while self.eat(t!("::")) {
			self.next_token_value::<Ident>()?;
			last_span = self.last_span();
		}

		let span = start.covers(last_span);
		let slice = self.lexer.reader.span(span);

		// parser implementations guarentess that the slice is a valid utf8 string.
		let str = std::str::from_utf8(slice).unwrap();

		match PATHS.get_entry(&UniCase::ascii(str)) {
			Some((_, PathKind::Constant(x))) => Ok(Value::Constant(x.clone())),
			Some((k, PathKind::Function)) => self
				.parse_builtin_function(k.into_inner().to_owned())
				.map(|x| Value::Function(Box::new(x))),
			None => {
				// Generate an suggestion.
				// don't search further if the levenshtein distance is further then 10.
				let mut cut_off = MAX_LEVENSTHEIN_CUT_OFF;

				let possibly = PATHS
					.keys()
					.copied()
					.min_by_key(|x| {
						let res = levenshtein(str.as_bytes(), x.as_bytes(), cut_off);
						cut_off = res.min(cut_off);
						res
					})
					.map(|x| x.into_inner());

				if cut_off == MAX_LEVENSTHEIN_CUT_OFF {
					// couldn't find a value which lowered the cut off,
					// any suggestion probably will be nonsensical so don't give any.
					return Err(ParseError::new(
						ParseErrorKind::InvalidPath {
							possibly: None,
						},
						span,
					));
				}

				Err(ParseError::new(
					ParseErrorKind::InvalidPath {
						possibly,
					},
					span,
				))
			}
		}
	}