type alias for Tokens

This commit is contained in:
greg 2015-07-22 03:36:32 -07:00
parent 67eafba97a
commit cea29094cd

View File

@ -17,9 +17,10 @@ pub enum ParseResult {
Err(String)
}
type Tokens<'a> = Iter<'a,Token>;
macro_rules! expect {
($tok:expr, $tokens:expr) => ( if !expect_token($tok, $tokens) {
println!("yo hitting");
return ParseResult::Err(format!("Expected {:?}", $tok));
})
}
@ -36,7 +37,7 @@ pub fn parse(input: Vec<Token>) -> ParseResult {
return ParseResult::Err("Bad parse".to_string());
}
fn expect_token(tok: Token, tokens: &mut Iter<Token>) -> bool {
fn expect_token(tok: Token, tokens: &mut Tokens) -> bool {
if let Some(n) = tokens.next() {
let next = (*n).clone();
return match (tok, next) {
@ -55,7 +56,7 @@ fn expect_token(tok: Token, tokens: &mut Iter<Token>) -> bool {
return false;
}
fn let_expression<'a>(input: &mut Iter<Token>) -> ParseResult {
fn let_expression(input: &mut Tokens) -> ParseResult {
expect!(Identifier("let".to_string()), input);
if let Some(&Identifier(ref name)) = input.next() {
if let Some(&Identifier(ref s)) = input.next() {