Split tokenizer

src/main.rs

@@ -73,7 +73,7 @@ fn main() -> Result<(), std::io::Error> {
 
 						RawTerminal::suspend_raw_mode(&stdout)?;
 						write!(stdout, "\n")?;
-						let g = parser::parse(&s);
+						let g = parser::evaluate(&s);
 						RawTerminal::activate_raw_mode(&stdout)?;
 
 						match g {

src/parser.rs

@@ -1,10 +1,12 @@
 mod tokenize;
 mod treeify;
+mod groupify;
 mod evaluate;
 
-use crate::parser::tokenize::tokenize;
+use crate::parser::tokenize::p_tokenize;
-use crate::parser::treeify::treeify;
+use crate::parser::groupify::p_groupify;
-use crate::parser::evaluate::evaluate;
+use crate::parser::treeify::p_treeify;
+use crate::parser::evaluate::p_evaluate;
 
 use std::collections::VecDeque;
 
@@ -29,6 +31,8 @@ pub enum Token {
 	/// Each of these will become one of the operators below.
 	PreOperator(LineLocation, Operator),
 
+	PreGroupStart(LineLocation),
+	PreGroupEnd(LineLocation),
 	/// Used only until operators are parsed.
 	/// PreGroups aren't needed once we have a tree.
 	PreGroup(LineLocation, VecDeque<Token>),
@@ -212,7 +216,6 @@ pub struct LineLocation {
 /// If we cannot parse a string, one of these is returned.
 #[derive(Debug)]
 pub enum ParserError {
-	InvalidChar,
 	MissingCloseParen,
 	ExtraCloseParen,
 	EmptyGroup,
@@ -233,11 +236,12 @@ pub enum ParserError {
 /// *what* the error is.
 /// 
 /// - `Ok(Token)` otherwise, where `Token` is the top of an expression tree.
-pub fn parse(s: &String) -> Result<Token, (LineLocation, ParserError)> {
+pub fn evaluate(s: &String) -> Result<Token, (LineLocation, ParserError)> {
 
-	let mut g: Token = tokenize(s)?;
+	let tokens = p_tokenize(s);
-	g = treeify(g)?;
+	let mut g = p_groupify(tokens)?;
-	g = evaluate(g)?;
+	g = p_treeify(g)?;
+	g = p_evaluate(g)?;
 
 	return Ok(g);
 }

src/parser/evaluate.rs

@@ -26,7 +26,7 @@ fn get_at_coords<'a>(g: &'a mut Token, coords: &Vec<usize>) -> &'a mut Token {
 }
 
 
-pub fn evaluate(
+pub fn p_evaluate(
 	mut g: Token,
 ) -> Result<Token, (LineLocation, ParserError)> {
 	let mut coords: Vec<usize> = Vec::with_capacity(16);
@@ -89,6 +89,8 @@ pub fn evaluate(
 			Token::PreWord(_,_) |
 			Token::PreOperator(_,_) |
 			Token::PreGroup(_,_) |
+			Token::PreGroupStart(_) |
+			Token::PreGroupEnd(_) |
 			Token::Root(_)
 			=> panic!()
 		};

src/parser/groupify.rs

@@ -0,0 +1,145 @@
+use std::collections::VecDeque;
+
+use crate::parser::Token;
+use crate::parser::LineLocation;
+use crate::parser::ParserError;
+use crate::parser::Operator;
+
+/// Looks backwards at the elements of g.
+/// - Inserts ImplicitMultiply
+/// - Removes multiple PreNegatives
+/// - Applies PreNegative to Numbers
+/// - Parses factorials
+/// - Checks syntax
+#[inline(always)]
+fn lookback(
+	g: &mut VecDeque<Token>
+) -> Result<(), (LineLocation, ParserError)> {
+	if g.len() >= 2 {
+		let b: Token = g.pop_back().unwrap();
+		let a: Token = g.pop_back().unwrap();
+
+		match (&a, &b) {
+			// Insert ImplicitMultiply
+			(Token::PreGroup(_,_), Token::PreGroup(l ,_)) |
+			(Token::PreGroup(_,_), Token::Number(l,_)) |
+			(Token::Number(_,_), Token::PreGroup(l,_)) |
+			(Token::Constant(_,_,_), Token::Number(l,_)) |
+			(Token::Number(_,_), Token::Constant(l,_,_)) |
+			(Token::Constant(_,_,_), Token::PreGroup(l,_)) |
+			(Token::PreGroup(_,_), Token::Constant(l,_,_)) |
+			(Token::Constant(_,_,_), Token::Constant(l,_,_))
+			=> {
+				g.push_back(a);
+				let LineLocation { pos: i, .. } = l;
+				g.push_back(Token::PreOperator(
+					LineLocation{pos: i-1, len: 0},
+					Operator::ImplicitMultiply
+				));
+				g.push_back(b);
+			},
+
+			// The following are syntax errors
+			(Token::Number(la, _), Token::Number(lb,_))
+			=> {
+				let LineLocation { pos: posa, .. } = *la;
+				let LineLocation { pos: posb, len: lenb } = *lb;
+				return Err((
+					LineLocation{pos: posa, len: posb - posa + lenb},
+					ParserError::Syntax
+				));
+			}
+
+			// The following are fine
+			(Token::PreOperator(_,_), _) |
+			(_, Token::PreOperator(_,_))
+			=> { g.push_back(a); g.push_back(b); },
+
+			// If we get this far, we found a Token
+			// that shouldn't be here.
+			_ => panic!()
+		}
+	};
+	return Ok(());
+}
+
+
+pub fn p_groupify(mut g: VecDeque<Token>) -> Result<Token, (LineLocation, ParserError)> {
+	// Vector of grouping levels
+	let mut levels: Vec<(LineLocation, VecDeque<Token>)> = Vec::with_capacity(8);
+	levels.push((LineLocation{pos: 0, len: 0}, VecDeque::with_capacity(8)));
+
+	// Makes sure parenthesis are matched
+	let mut i_level = 0;
+
+	while g.len() > 0 {
+		let t = g.pop_front().unwrap();
+		let (l_now, v_now) = levels.last_mut().unwrap();
+
+		match &t {
+			Token::PreOperator(_, _) => {
+				v_now.push_back(t);
+				lookback(v_now)?;
+			},
+
+			Token::PreNumber(l, s) => {
+				let n = match s.parse() {
+					Ok(n) => n,
+					Err(_) => return Err((*l, ParserError::BadNumber))
+				};
+				v_now.push_back(Token::Number(*l, n));
+				lookback(v_now)?;
+			},
+
+			Token::PreWord(l, s) => {
+				v_now.push_back(match &s[..] {
+					"mod" => { Token::PreOperator(*l, Operator::ModuloLong) },
+					"pi" => { Token::Constant(*l, 3.141592653, String::from("π")) },
+					_ => { return Err((*l, ParserError::Syntax)); }
+				});
+				lookback(v_now)?;
+			},
+
+			Token::PreGroupStart(l) => {
+				levels.push((*l, VecDeque::with_capacity(8)));
+				i_level += 1;
+			},
+
+			Token::PreGroupEnd(l) => {
+				let LineLocation{pos: posa, ..} = *l_now;
+				let LineLocation{pos: posb, len: lenb} = l;
+
+				let l = LineLocation {
+					pos: posa,
+					len: lenb + posb - posa
+				};
+
+				if i_level == 0 {
+					return Err((l, ParserError::ExtraCloseParen))
+				}
+				i_level -= 1;
+
+				// Catch empty groups
+				if v_now.len() == 0 {
+					return Err((l, ParserError::EmptyGroup))
+				}
+
+				let (_, v) = levels.pop().unwrap();
+				let (_, v_now) = levels.last_mut().unwrap();
+
+				v_now.push_back(Token::PreGroup(l, v));
+				lookback(v_now)?;
+			},
+
+			_ => panic!()
+		}
+	}
+
+	if levels.len() != 1 {
+		let (l, _) = levels.pop().unwrap();
+		return Err((l, ParserError::MissingCloseParen))
+	}
+
+	let (_, v) = levels.pop().unwrap();
+	return Ok(Token::Root(v));
+}

src/parser/tokenize.rs

@@ -2,7 +2,6 @@ use std::collections::VecDeque;
 
 use crate::parser::Token;
 use crate::parser::LineLocation;
-use crate::parser::ParserError;
 use crate::parser::Operator;
 
 /// Updates the length of a Token's LineLocation.
@@ -10,7 +9,8 @@ use crate::parser::Operator;
 #[inline(always)]
 fn update_line_location(mut t: Token, stop_i: usize) -> Token {
 	match t {
-		Token::PreGroup(ref mut l, _) |
+		Token::PreGroupStart(ref mut l) |
+		Token::PreGroupEnd(ref mut l) |
 		Token::PreOperator(ref mut l, _) |
 		Token::PreNumber(ref mut l, _) |
 		Token::PreWord(ref mut l, _)
@@ -27,137 +27,20 @@ fn update_line_location(mut t: Token, stop_i: usize) -> Token {
 	return t;
 }
 
-
-/// Looks backwards at the elements of g.
-/// - Inserts ImplicitMultiply
-/// - Removes multiple PreNegatives
-/// - Applies PreNegative to Numbers
-/// - Parses factorials
-/// - Checks syntax
-#[inline(always)]
-fn lookback(
-	g: &mut VecDeque<Token>
-) -> Result<(), (LineLocation, ParserError)> {
-	if g.len() >= 2 {
-		let b: Token = g.pop_back().unwrap();
-		let a: Token = g.pop_back().unwrap();
-
-		match (&a, &b) {
-			// Insert ImplicitMultiply
-			(Token::PreGroup(_,_), Token::PreGroup(l ,_)) |
-			(Token::PreGroup(_,_), Token::Number(l,_)) |
-			(Token::Number(_,_), Token::PreGroup(l,_)) |
-			(Token::Constant(_,_,_), Token::Number(l,_)) |
-			(Token::Number(_,_), Token::Constant(l,_,_)) |
-			(Token::Constant(_,_,_), Token::PreGroup(l,_)) |
-			(Token::PreGroup(_,_), Token::Constant(l,_,_)) |
-			(Token::Constant(_,_,_), Token::Constant(l,_,_))
-			=> {
-				g.push_back(a);
-				let LineLocation { pos: i, .. } = l;
-				g.push_back(Token::PreOperator(
-					LineLocation{pos: i-1, len: 0},
-					Operator::ImplicitMultiply
-				));
-				g.push_back(b);
-			},
-
-			// The following are syntax errors
-			(Token::Number(la, _), Token::Number(lb,_))
-			=> {
-				let LineLocation { pos: posa, .. } = *la;
-				let LineLocation { pos: posb, len: lenb } = *lb;
-				return Err((
-					LineLocation{pos: posa, len: posb - posa + lenb},
-					ParserError::Syntax
-				));
-			}
-
-			// The following are fine
-			(Token::PreOperator(_,_), _) |
-			(_, Token::PreOperator(_,_))
-			=> { g.push_back(a); g.push_back(b); },
-
-			// If we get this far, we found a Token
-			// that shouldn't be here.
-			_ => panic!()
-		}
-	};
-	return Ok(());
-}
-
-
-
-/// Pushes (and potentially processes) a token we just read to a vector.
-/// - Converts all `PreNumbers` to `Numbers`, returning a BadNumber error if necessary
-/// - Converts all `PreWords` to other tokens.
-fn push_token(
-	g_now: &mut VecDeque<Token>,
-	i: usize,
-	t: Option<Token>
-) -> Result<(), (LineLocation, ParserError)>{
-	if t.is_none() {
-		return Ok(());
-	} else {
-		let t: Token = update_line_location(t.unwrap(), i);
-		g_now.push_back(match t {
-			Token::PreNumber(l, s) => {
-				let n = match s.parse() {
-					Ok(n) => n,
-					Err(_) => return Err((l, ParserError::BadNumber))
-				};
-				Token::Number(l, n)
-			},
-			Token::PreWord(l, s) => {
-				if s == "mod" {
-					Token::PreOperator(l, Operator::ModuloLong)
-				} else if s == "pi" {
-					Token::Constant(l, 3.141592653, String::from("π"))
-				} else {
-					return Err((l, ParserError::Syntax));
-				}
-			},
-			Token::PreOperator(_, _) => t,
-			Token::PreGroup(_, _) => t,
-			_ => panic!()
-		});
-
-		lookback(g_now)?;
-	}
-	return Ok(());
-}
-
-
 /// Turns a string into Tokens. First stage of parsing.
-pub fn tokenize(input: &String) -> Result<Token, (LineLocation, ParserError)> {
+pub fn p_tokenize(input: &String) -> VecDeque<Token> {
 	let mut t: Option<Token> = None; // The current token we're reading
-	let mut g: Vec<Token> = Vec::with_capacity(8); // Vector of "grouping levels"
+	let mut g: VecDeque<Token> = VecDeque::with_capacity(32); 
-	let mut i_level = 0;
-	g.push(Token::PreGroup(LineLocation{pos: 0, len: 0}, VecDeque::with_capacity(8)));
 
 
 	for (i, c) in input.chars().enumerate() {
 
-		// The grouping level we're on now
-		let g_now: &mut VecDeque<Token> = match g.last_mut().unwrap() {
-			Token::PreGroup(_, ref mut x) => x,
-			_ => panic!()
-		};
-
 		match c {
-			'!' => {
-				push_token(g_now, i, t)?;
-				t = Some(Token::PreOperator(
-					LineLocation{pos: i, len: 1},
-					Operator::Factorial
-				));
-			},
-
 			// The minus sign can be both a Negative and an Operator.
 			// Needs special treatment.
 			'-' => {
-				push_token(g_now, i, t)?;
+				if t.is_some() { g.push_back(update_line_location(t.unwrap(), i)); }
-				match g_now.back() {
+				match g.back() {
 					// If previous token was any of the following,
 					// this is the "minus" operator
 					Some(Token::Number(_, _)) |
@@ -192,42 +75,28 @@ pub fn tokenize(input: &String) -> Result<Token, (LineLocation, ParserError)> {
 					// If we're not building a number, finalize
 					// previous token and start one.
 					_ => {
-						push_token(g_now, i, t)?;
+						if t.is_some() { g.push_back(update_line_location(t.unwrap(), i)); }
 						t = Some(Token::PreNumber(LineLocation{pos: i, len: 0}, String::from(c)));
 					}
 				};
 			},
 
-			// Word
-			'A'..='Z' |
-			'a'..='z' => {
-				match &mut t {
-					Some(Token::PreWord(_, val)) => {
-						val.push(c);
-					},
-
-					_ => {
-						push_token(g_now, i, t)?;
-						t = Some(Token::PreWord(LineLocation{pos: i, len: 0}, String::from(c)));
-					}
-				};
-			},
-
 			// Operator
 			// Always one character
-			
 			'*'|'×'|
 			'/'|'÷'|
-			'+'|'%'|'^' => {
+			'+'|'%'|
-				push_token(g_now, i, t)?;
+			'^'|'!' => {
+				if t.is_some() { g.push_back(update_line_location(t.unwrap(), i)); }
 				t = Some(Token::PreOperator(
-					LineLocation{pos: i, len: 1},
+					LineLocation{pos: i, len: 0},
 					match c {
 						'^' => Operator::Power,
 						'%' => Operator::Modulo,
 						'*'|'×' => Operator::Multiply,
 						'/'|'÷' => Operator::Divide,
 						'+' => Operator::Add,
+						'!' => Operator::Factorial,
 						_ => panic!()
 					}
 				));
@@ -235,67 +104,41 @@ pub fn tokenize(input: &String) -> Result<Token, (LineLocation, ParserError)> {
 			
 			// Group
 			'(' => {
-				push_token(g_now, i, t)?; t = None;
+				if t.is_some() { g.push_back(update_line_location(t.unwrap(), i)); }
-				g.push(Token::PreGroup(LineLocation{pos: i, len: 0}, VecDeque::with_capacity(8)));
+				t = Some(Token::PreGroupStart(LineLocation{pos: i, len: 0}));
-				i_level += 1;
 			},
 			')' => {
-				// Catch extra close parens
+				if t.is_some() { g.push_back(update_line_location(t.unwrap(), i)); }
-				if i_level == 0 {
+				t = Some(Token::PreGroupEnd(LineLocation{pos: i, len: 0}));
-					return Err((
-						LineLocation{pos: i, len: 1},
-						ParserError::ExtraCloseParen
-					))
-				}
-				i_level -= 1;
-
-				// Catch empty groups
-				if t.is_none() {
-					let mut last = g.pop().unwrap();
-					last = update_line_location(last, i+1);
-					let Token::PreGroup(l, _) = last else {panic!()};
-					return Err((
-						l,
-						ParserError::EmptyGroup
-					))
-				}
-
-				push_token(g_now, i, t)?;
-				t = Some(g.pop().unwrap());
 			},
 
 			// Space. Basic seperator.
 			' ' => {
-				push_token(g_now, i, t)?; t = None;
+				if t.is_some() {
+					g.push_back(update_line_location(t.unwrap(), i));
+					t = None;
+				}
 			}
 
-			// Invalid character
+			// Word
-			_ => { return Err((LineLocation{pos: i, len: 1}, ParserError::InvalidChar)); }
+			//'A'..='Z' |
+			//'a'..='z' 
+			_ => {
+				match &mut t {
+					Some(Token::PreWord(_, val)) => {
+						val.push(c);
+					},
+
+					_ => {
+						if t.is_some() { g.push_back(update_line_location(t.unwrap(), i)); }
+						t = Some(Token::PreWord(LineLocation{pos: i, len: 0}, String::from(c)));
+					}
+				};
+			}
 		};
 	}
 
+	if t.is_some() { g.push_back(update_line_location(t.unwrap(), input.len())); }
 
-	let g_now: &mut VecDeque<Token> = match g.last_mut().unwrap() {
+	return g;
-		Token::PreGroup(_, ref mut x) => x,
-		_ => panic!()
-	};
-	push_token(g_now, input.len(), t)?;
-
-	if g.len() != 1 {
-		let q: LineLocation = match g.last_mut().unwrap() {
-			Token::PreGroup(l, _) => *l,
-			_ => panic!()
-		};
-
-		let LineLocation{pos:p, ..} = q;
-		return Err((
-			LineLocation{
-				pos: p,
-				len: input.len() - p
-			},
-			ParserError::MissingCloseParen
-		))
-	}
-
-	return Ok(g.pop().unwrap());
 }

src/parser/treeify.rs

@@ -346,7 +346,7 @@ fn inner_treeify(
 ) -> Result<Token, (LineLocation, ParserError)> {
 
 	let g_inner: &mut VecDeque<Token> = match g {
-		Token::PreGroup(_, ref mut x) => x,
+		Token::Root(ref mut x) => x,
 		_ => panic!()
 	};
 
@@ -394,7 +394,7 @@ fn inner_treeify(
 	return Ok(g);
 }
 
-pub fn treeify(
+pub fn p_treeify(
 	mut g: Token,
 ) -> Result<Token, (LineLocation, ParserError)> {
 	let mut v: VecDeque<Token> = VecDeque::new();