improve number lexing (temporarily breaking function lexing)

This commit is contained in:
Book-reader 2025-09-05 22:26:06 +12:00
parent adf97d4b20
commit cbf35e9746

View file

@ -156,7 +156,8 @@ enum ParseErr {
struct Lexer<'a> {
data: &'a str,
data_ptr: &'a str,
idx: usize,
// idx: usize,
next_by: usize,
next_tok: Result<Token, ParseErr>,
}
@ -164,20 +165,18 @@ struct Lexer<'a> {
impl Lexer<'_> {
fn new(data: &str) -> Lexer<'_> {
let mut n: Lexer = Lexer {data, data_ptr: data, idx: 0, next_tok: Err(ParseErr::Eof)};
let mut n: Lexer = Lexer {data, data_ptr: data, next_by: 0, next_tok: Err(ParseErr::Eof)};
n.next();
debug!("New finished!");
n
}
fn _next(&mut self) -> Result<Token, ParseErr> {
match self.data.chars().nth(self.idx) {
self.data_ptr = &self.data_ptr[self.next_by..];
match self.data_ptr.chars().nth(0) {
Some(val) => {
debug!("lexing char '{}' at idx {}", val, self.idx);
// debug!("current char '{}'", self.data.chars().nth(0).unwrap());
self.idx += 1;
// TODO: make more efficient
self.data_ptr = &self.data[self.idx..];
debug!("lexing char '{}' at idx {}", val, self.data.chars().count() - self.data_ptr.chars().count());
self.next_by = 1;
match val {
'+' => Ok(Token::Op(Op::Add)),
'-' => Ok(Token::Op(Op::Subtract)),
@ -187,18 +186,20 @@ impl Lexer<'_> {
'(' => Ok(Token::Op(Op::LParen)),
')' => Ok(Token::Op(Op::RParen)),
_ if val.is_whitespace() => self._next(),
// TODO: maybe parse '-' as part of number so I can do '1 + -1' and similar
_ if val.is_digit(10) => {
let start = self.idx - 1;
let mut len: usize = 0;
self.data_ptr.chars().take_while(|c| c.is_digit(10) || *c == '.').for_each(|_| len += 1);
self.next_by += len - 1;
self.data_ptr.chars().take_while(|c| c.is_digit(10)).for_each(|_| self.idx += 1);//.next().unwrap_or(' ').is_digit(10) {self.idx += 1;}
match self.data[start..self.idx].parse() {
match self.data_ptr[..len].parse() {
Ok(val) => Ok(Token::Atom(Atom::Number(val))),
Err(e) => Err(ParseErr::Invalid),
}
},
_ => {
/* match (&self.data[self.idx - 1..]) {
s if s.starts_with(""
}
let mut l: usize;
l = matches(&self.data[self.idx - 1..], "sin");
if l != 0 {
@ -235,13 +236,16 @@ impl Lexer<'_> {
self.idx += l;
return Ok(Token::Op(Op::Func(Func::SquareRoot)));
}
*/
debug!("got invalid char '{}'", val);
Err(ParseErr::Invalid)
}
}
}
None => Err(ParseErr::Eof),
None => {
self.next_by = 0;
Err(ParseErr::Eof)
},
}
}