126 lines
3.2 KiB
Rust
126 lines
3.2 KiB
Rust
use std::fmt::Debug;
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use super::CharCursor;
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#[derive(PartialEq, Eq, Clone, Copy)]
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pub enum Symbol {
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Semicolon,
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Colon,
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DoubleColon,
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Equals,
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DoubleEquals,
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Arrow,
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DoubleArrow,
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Plus,
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Minus,
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Asterisk,
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Slash,
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DoubleSlash,
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Dot,
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OpenParen,
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CloseParen,
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OpenCurly,
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CloseCurly,
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OpenSquare,
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CloseSquare,
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OpenAngle,
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CloseAngle,
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SingleQuote,
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DoubleQuote,
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Bang,
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}
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impl Symbol {
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pub fn parse(cursor: &mut CharCursor) -> Option<Self> {
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Self::from_char(cursor.peek()?).map(|mut s| {
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cursor.advance();
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s.finish(cursor);
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s
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})
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}
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pub fn from_char(c: char) -> Option<Self> {
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Some(match c {
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'(' => Self::OpenParen,
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')' => Self::CloseParen,
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'[' => Self::OpenSquare,
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']' => Self::CloseSquare,
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'{' => Self::OpenCurly,
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'}' => Self::CloseCurly,
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'<' => Self::OpenAngle,
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'>' => Self::CloseAngle,
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';' => Self::Semicolon,
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':' => Self::Colon,
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'+' => Self::Plus,
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'-' => Self::Minus,
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'*' => Self::Asterisk,
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'/' => Self::Slash,
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'=' => Self::Equals,
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'.' => Self::Dot,
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'\'' => Self::SingleQuote,
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'"' => Self::DoubleQuote,
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'!' => Self::Bang,
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_ => return None,
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})
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}
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pub fn finish(&mut self, cursor: &mut CharCursor) {
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let Some(next) = cursor.peek() else {
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return;
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};
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*self = match self {
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Self::Colon => match next {
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':' => Self::DoubleColon,
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_ => return,
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},
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Self::Minus => match next {
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'>' => Self::Arrow,
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_ => return,
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},
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Self::Equals => match next {
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'=' => Self::DoubleEquals,
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'>' => Self::DoubleArrow,
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_ => return,
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}
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Self::Slash => match next {
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'/' => Self::DoubleSlash,
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_ => return,
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}
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_ => return,
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};
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cursor.advance();
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}
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pub fn str(&self) -> &str {
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match self {
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Self::Semicolon => ";",
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Self::Colon => ":",
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Self::DoubleColon => "::",
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Self::Equals => "=",
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Self::DoubleEquals => "==",
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Self::Arrow => "->",
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Self::DoubleArrow => "=>",
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Self::Plus => "+",
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Self::Minus => "-",
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Self::Asterisk => "*",
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Self::Slash => "/",
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Self::DoubleSlash => "//",
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Self::Dot => ".",
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Self::OpenParen => "(",
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Self::CloseParen => ")",
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Self::OpenCurly => "{",
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Self::CloseCurly => "}",
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Self::OpenSquare => "[",
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Self::CloseSquare => "]",
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Self::OpenAngle => "<",
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Self::CloseAngle => ">",
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Self::SingleQuote => "'",
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Self::DoubleQuote => "\"",
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Self::Bang => "!",
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}
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}
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}
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impl Debug for Symbol {
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fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
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write!(f, "'{}'", self.str())
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}
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}
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