Added prompt replacement

src/main.rs

@@ -12,7 +12,7 @@ use crate::promptbuffer::PromptBuffer;
 
 use crate::parser::Token;
 //use crate::parser::ParserError;
-use crate::parser::LineLocation;
+//use crate::parser::LineLocation;
 
 
 fn draw_line(
@@ -54,14 +54,13 @@ fn main() -> Result<(), std::io::Error> {
 
 	'outer: loop {
 
+		let s = parser::substitute(&pb.get_contents());
 		draw_line(
-			&mut stdout,
-			pb.get_contents(),
-			if pb.get_contents().len() >= last_len
-			{ 0 } else {last_len - pb.get_contents().len()}
+			&mut stdout, &s,
+			if s.chars().count() >= last_len
+			{ 0 } else {last_len - s.chars().count()}
 		)?;
-		last_len = pb.get_contents().len();
-		
+		last_len = s.chars().count();
 
 		let stdin = stdin();
 		for c in stdin.keys() {
@@ -102,8 +101,6 @@ fn main() -> Result<(), std::io::Error> {
 
 						break;
 					},
-					'/' => { pb.add_char('÷'); },
-					'*' => { pb.add_char('×'); },
 					_ => { pb.add_char(*q); }
 				};
 			} else {
@@ -121,13 +118,13 @@ fn main() -> Result<(), std::io::Error> {
 				};
 			};
 
+			let s = parser::substitute(&pb.get_contents());
 			draw_line(
-				&mut stdout,
-				pb.get_contents(),
-				if pb.get_contents().len() >= last_len
-				{ 0 } else {last_len - pb.get_contents().len()}
+				&mut stdout, &s,
+				if s.chars().count() >= last_len
+				{ 0 } else {last_len - s.chars().count()}
 			)?;
-			last_len = pb.get_contents().len();
+			last_len = s.chars().count();
 		}
 	}
 

src/parser.rs

@@ -2,11 +2,13 @@ mod tokenize;
 mod treeify;
 mod groupify;
 mod evaluate;
+mod find_subs;
 
 use crate::parser::tokenize::p_tokenize;
 use crate::parser::groupify::p_groupify;
 use crate::parser::treeify::p_treeify;
 use crate::parser::evaluate::p_evaluate;
+use crate::parser::find_subs::p_find_subs;
 
 use std::collections::VecDeque;
 
@@ -264,4 +266,22 @@ pub fn evaluate(s: &String) -> Result<Token, (LineLocation, ParserError)> {
 	g = p_evaluate(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/find_subs.rs

@@ -0,0 +1,66 @@
+use std::collections::VecDeque;
+
+use crate::parser::Operator;
+use crate::parser::Token;
+use crate::parser::LineLocation;
+
+
+pub fn p_find_subs(
+	mut g: VecDeque<Token>,
+) -> Vec<(LineLocation, String)> {
+
+	let mut r: Vec<(LineLocation, String)> = Vec::with_capacity(8);
+
+	while g.len() > 0 {
+		// Read in reverse. Very important!
+		let t = g.pop_back().unwrap();
+
+		match &t {
+
+			Token::PreOperator(l, o) => {
+				match o {
+					Operator::Multiply => { r.push((l.clone(), String::from("×"))); },
+					Operator::Divide => { r.push((l.clone(), String::from("÷"))); },
+					_ => {}
+				}
+			},
+
+			Token::PreWord(l, s) => {
+				match &s[..] {
+
+					// Greek letters
+					"alpha"   => { r.push((l.clone(), String::from("α"))); },
+					"beta"    => { r.push((l.clone(), String::from("β"))); },
+					"gamma"   => { r.push((l.clone(), String::from("γ"))); },
+					"delta"   => { r.push((l.clone(), String::from("δ"))); },
+					"epsilon" => { r.push((l.clone(), String::from("ε"))); },
+					"zeta"    => { r.push((l.clone(), String::from("ζ"))); },
+					"eta"     => { r.push((l.clone(), String::from("η"))); },
+					"theta"   => { r.push((l.clone(), String::from("θ"))); },
+					"iota"    => { r.push((l.clone(), String::from("ι"))); },
+					//"kappa"   => { r.push((l.clone(), String::from("κ"))); },
+					"lambda"  => { r.push((l.clone(), String::from("λ"))); },
+					"mu"      => { r.push((l.clone(), String::from("μ"))); },
+					"nu"      => { r.push((l.clone(), String::from("ν"))); },
+					"xi"      => { r.push((l.clone(), String::from("ξ"))); },
+					//"omicron" => { r.push((l.clone(), String::from("ο"))); },
+					"pi"      => { r.push((l.clone(), String::from("π"))); },
+					"rho"     => { r.push((l.clone(), String::from("ρ"))); },
+					"sigma"   => { r.push((l.clone(), String::from("σ"))); },
+					"tau"     => { r.push((l.clone(), String::from("τ"))); },
+					//"upsilon" => { r.push((l.clone(), String::from("υ"))); },
+					"phi"     => { r.push((l.clone(), String::from("φ"))); },
+					"chi"     => { r.push((l.clone(), String::from("χ"))); },
+					"psi"     => { r.push((l.clone(), String::from("ψ"))); },
+					"omega"   => { r.push((l.clone(), String::from("ω"))); }
+
+					_ => {}
+				}
+
+			}
+			_ => {}
+		}
+	}
+
+	return r;
+}

src/parser/tokenize.rs

@@ -82,10 +82,9 @@ pub fn p_tokenize(input: &String) -> VecDeque<Token> {
 
 			// Operator
 			// Always one character
-			'*'|'×'|
-			'/'|'÷'|
-			'+'|'%'|
-			'^'|'!' => {
+			'*'|'/'|'+'|
+			'^'|'!'|'%'
+			=> {
 				if t.is_some() { g.push_back(update_line_location(t.unwrap(), i)); }
 				t = Some(Token::PreOperator(
 					LineLocation{pos: i, len: 0},