Restructured code

src/parser/evaluate.rs

@@ -1,79 +0,0 @@
-use crate::parser::Token;
-use crate::parser::LineLocation;
-use crate::parser::ParserError;
-
-#[inline(always)]
-fn get_at_coords<'a>(g: &'a mut Token, coords: &Vec<usize>) -> &'a mut Token {
-	let mut h = &mut *g;
-
-	for t in coords.iter() {
-		let inner = h.get_args().unwrap();
-		h = &mut inner[*t];
-	}
-
-	return h;
-}
-
-
-pub fn p_evaluate(
-	mut g: Token,
-) -> Result<Token, (LineLocation, ParserError)> {
-	let mut coords: Vec<usize> = Vec::with_capacity(16);
-	coords.push(0);
-
-	'outer: loop {
-
-		let mut h = &mut g;
-		for t in coords.iter() {
-			let inner = h.get_args();
-
-			if inner.is_none() || *t >= inner.as_ref().unwrap().len() {
-				coords.pop();
-				if coords.len() == 0 { break 'outer; }
-
-
-				let p = get_at_coords(&mut g, &coords);
-				let e = p.eval();
-				*p = e;
-
-				let l = coords.pop().unwrap();
-				coords.push(l + 1);
-				continue 'outer;
-			}
-
-			h = &mut inner.unwrap()[*t];
-		}
-
-		match h {
-			Token::Multiply(_) |
-			Token::Divide(_) |
-			Token::Add(_) |
-			Token::Factorial(_) |
-			Token::Negative(_) |
-			Token::Power(_) |
-			Token::Modulo(_)
-			=> {
-				coords.push(0);
-				continue 'outer;
-			},
-
-			Token::Constant(_,_,_) |
-			Token::Number(_,_) => {
-				let l = coords.pop().unwrap();
-				coords.push(l + 1);
-				continue 'outer;
-			}
-
-			Token::PreNumber(_,_) |
-			Token::PreWord(_,_) |
-			Token::PreOperator(_,_) |
-			Token::PreGroup(_,_) |
-			Token::PreGroupStart(_) |
-			Token::PreGroupEnd(_)
-			=> panic!()
-		};
-	}
-
-
-	return Ok(g);
-}

src/parser/find_subs.rs

@@ -1,8 +1,8 @@
 use std::collections::VecDeque;
 
-use crate::parser::Operator;
-use crate::parser::Token;
-use crate::parser::LineLocation;
+use crate::tokens::Token;
+use crate::tokens::Operator;
+use crate::tokens::LineLocation;
 
 
 pub fn p_find_subs(
@@ -60,6 +60,7 @@ pub fn p_find_subs(
 					"chi"     => {Some("χ")},
 					"psi"     => {Some("ψ")},
 					"omega"   => {Some("ω")},
+					"sqrt"    => {Some("√")},
 
 					_ => {None}
 				};

src/parser/groupify.rs

@@ -1,9 +1,10 @@
 use std::collections::VecDeque;
 
-use crate::parser::Token;
-use crate::parser::LineLocation;
+use crate::tokens::Token;
+use crate::tokens::Operator;
+use crate::tokens::LineLocation;
+
 use crate::parser::ParserError;
-use crate::parser::Operator;
 
 /// Looks backwards at the elements of g.
 /// - Inserts ImplicitMultiply

src/parser/mod.rs

@@ -0,0 +1,84 @@
+mod tokenize;
+mod treeify;
+mod groupify;
+mod find_subs;
+
+
+use crate::parser::tokenize::p_tokenize;
+use crate::parser::groupify::p_groupify;
+use crate::parser::treeify::p_treeify;
+use crate::parser::find_subs::p_find_subs;
+
+use crate::tokens;
+
+/// Types of parser errors.
+/// If we cannot parse a string, one of these is returned.
+#[derive(Debug)]
+pub enum ParserError {
+	//MissingCloseParen,
+	ExtraCloseParen,
+	EmptyGroup,
+	Syntax,
+	Undefined(String),
+	BadNumber
+}
+
+impl ParserError {
+	pub fn to_message(&self) -> String {
+		match self {
+			//ParserError::MissingCloseParen => {
+			//	String::from("This group is never closed")
+			//},
+			ParserError::ExtraCloseParen => {
+				String::from("Extra close parenthesis")
+			},
+			ParserError::EmptyGroup => {
+				String::from("Groups can't be empty")
+			},
+			ParserError::Syntax => {
+				String::from("Syntax")
+			},
+			ParserError::Undefined(s) => {
+				format!("\"{s}\" isn't defined")
+			},
+			ParserError::BadNumber => {
+				String::from("Invalid number")
+			}
+		}
+	}
+}
+
+
+
+pub fn parse(
+	s: &String
+) -> Result<
+	tokens::Token,
+	(tokens::LineLocation, ParserError)
+> {
+
+	let tokens = p_tokenize(s);
+	let (_, tokens) = p_find_subs(tokens);
+	let mut g = p_groupify(tokens)?;
+	g = p_treeify(g)?;
+
+	return Ok(g);
+}
+
+
+pub fn substitute(s: &String) -> String{
+	if s == "" { return s.clone() }
+	let mut new_s = s.clone();
+
+	let tokens = p_tokenize(s);
+	let (subs, _) = p_find_subs(tokens);
+
+	for r in subs.iter() {
+		new_s.replace_range(
+			r.0.pos..r.0.pos+r.0.len,
+			&r.1[..]
+		)
+	}
+
+	return new_s;
+}

src/parser/tokenize.rs

@@ -1,8 +1,8 @@
 use std::collections::VecDeque;
 
-use crate::parser::Token;
-use crate::parser::LineLocation;
-use crate::parser::Operator;
+use crate::tokens::Token;
+use crate::tokens::Operator;
+use crate::tokens::LineLocation;
 
 /// Updates the length of a Token's LineLocation.
 /// Run whenever a token is finished.

src/parser/treeify.rs

@@ -1,9 +1,10 @@
 use std::collections::VecDeque;
 
-use crate::parser::Token;
-use crate::parser::LineLocation;
+use crate::tokens::Token;
+use crate::tokens::Operator;
+use crate::tokens::LineLocation;
+
 use crate::parser::ParserError;
-use crate::parser::Operator;
 
 fn treeify_binary(
 	i: usize,