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mod error;
mod parse;
mod parsers;
mod tokens;
use std::collections::VecDeque;
pub use error::{MacrosError, ParseError, ParseErrorKind, ToMacrosError};
pub use parse::Parse;
use proc_macro2::{Span, TokenStream};
use quote::ToTokens;
pub use tokens::{Delimiter, Token};
#[derive(Clone, Debug, PartialEq, Eq)]
pub struct MacroStream {
stream: VecDeque<Token>,
popped: usize,
}
pub type ParseResult<T> = std::result::Result<T, ParseError>;
#[derive(Clone, Debug)]
pub enum Match {
One(Token),
Many(Vec<Match>),
None,
}
impl MacroStream {
pub fn new() -> Self {
Self {
stream: VecDeque::new(),
popped: 0,
}
}
pub fn popped(&self) -> usize {
self.popped
}
pub fn from_tokens(stream: TokenStream) -> ParseResult<Self> {
let mut tokens = VecDeque::new();
for i in stream.into_iter() {
tokens.push_back(i);
}
let mut stream = VecDeque::new();
while !tokens.is_empty() {
stream.push_back(Token::from_tokens(&mut tokens)?);
}
Ok(Self { stream, popped: 0 })
}
pub fn pop(&mut self) -> Option<Token> {
self.stream.pop_front()
}
pub fn peek(&self) -> Option<&Token> {
self.stream.front()
}
pub fn parse<T>(&mut self) -> Result<T, MacrosError>
where
T: Parse,
{
T::parse(self)
}
pub fn is_empty(&self) -> bool {
self.stream.is_empty()
}
pub fn pop_or_err(&mut self) -> Result<Token, ParseError> {
self.pop()
.ok_or_else(|| {
ParseError::call_site(ParseErrorKind::UnexpectedEndOfInput("".to_string()))
})
.map(|i| {
self.popped += 1;
i
})
}
pub fn peek_or_err(&self) -> Result<&Token, ParseError> {
self.peek().ok_or_else(|| {
ParseError::call_site(ParseErrorKind::UnexpectedEndOfInput("".to_string()))
})
}
pub fn push_front(&mut self, token: Token) {
self.stream.push_front(token)
}
pub fn push_back(&mut self, token: Token) {
self.stream.push_back(token)
}
pub fn len(&self) -> usize {
self.stream.len()
}
pub fn fork(&self) -> Self {
Self {
stream: self.stream.clone(),
popped: 0,
}
}
pub fn popped_off_fork(&mut self, p: usize) -> Self {
let mut popped = Self::new();
for _ in 0..p {
self.popped += 1;
popped.push_back(self.pop().unwrap());
}
popped
}
pub fn popped_off(&mut self, p: usize) {
for _ in 0..p {
self.pop().unwrap();
}
}
}
impl From<TokenStream> for MacroStream {
fn from(stream: TokenStream) -> Self {
Self::from_tokens(stream).unwrap()
}
}
impl Default for MacroStream {
fn default() -> Self {
Self::new()
}
}
impl ToTokens for MacroStream {
fn to_tokens(&self, tokens: &mut TokenStream) {
for i in &self.stream {
i.to_tokens(tokens);
}
}
}
pub fn call_site() -> Span {
Span::call_site()
}