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use unicode_xid::UnicodeXID;
use {Token, SyntaxKind};
use syntax_kinds::*;
mod ptr;
use self::ptr::Ptr;
pub fn next_token(text: &str) -> Token {
assert!(!text.is_empty());
let mut ptr = Ptr::new(text);
let c = ptr.bump().unwrap();
let kind = next_token_inner(c, &mut ptr);
let len = ptr.into_len();
Token { kind, len }
}
fn next_token_inner(c: char, ptr: &mut Ptr) -> SyntaxKind {
// Note: r as in r" or r#" is part of a raw string literal,
// b as in b' is part of a byte literal.
// They are not identifiers, and are handled further down.
let ident_start = ident_start(c) && !string_literal_start(c, ptr.next(), ptr.nnext());
if ident_start {
loop {
match ptr.next() {
Some(c) if ident_continue(c) => {
ptr.bump();
},
_ => break,
}
}
IDENT
} else {
WHITESPACE
}
}
fn ident_start(c: char) -> bool {
(c >= 'a' && c <= 'z')
|| (c >= 'A' && c <= 'Z')
|| c == '_'
|| (c > '\x7f' && UnicodeXID::is_xid_start(c))
}
fn ident_continue(c: char) -> bool {
(c >= 'a' && c <= 'z')
|| (c >= 'A' && c <= 'Z')
|| (c >= '0' && c <= '9')
|| c == '_'
|| (c > '\x7f' && UnicodeXID::is_xid_continue(c))
}
fn string_literal_start(c: char, c1: Option<char>, c2: Option<char>) -> bool {
match (c, c1, c2) {
('r', Some('"'), _) |
('r', Some('#'), _) |
('b', Some('"'), _) |
('b', Some('\''), _) |
('b', Some('r'), Some('"')) |
('b', Some('r'), Some('#')) => true,
_ => false
}
}
|
