Added terminal color detection

Added configuration
Cleaned up context args

src/command/mod.rs

@@ -170,7 +170,7 @@ pub fn do_command(
 
 					t.push(&format!(
 						"  {key}{padding} = [c]{v}[n]\n",
-						v = value.to_string(),
+						v = value.display(context),
 					));
 				}
 			}
@@ -184,7 +184,7 @@ pub fn do_command(
 
 					t.push(&format!(
 						"  {s}{padding} = [c]{v}[n]\n",
-						v = exp.to_string(),
+						v = exp.display(context),
 					));
 				}
 			}

src/context.rs

@@ -3,7 +3,68 @@ use crate::quantity::freeunit_from_string;
 use std::collections::HashMap;
 
 #[derive(Debug)]
+#[derive(Clone)]
+pub struct Config {
+
+	// How to color terminal text.
+	// 0: No colors
+	// 1: ANSI-compatible, 8 colors
+	// 2: Full 256 color and special styles
+	pub term_color_type: u8,
+
+	// Should we accept input and print in unicode?
+	//pub enable_unicode: bool,
+
+	// Should we replace certain strings (like "pi")
+	// with prettier unicode alternatives?
+	//
+	// Automatically disabled if enable_unicode is off.
+	//pub enable_substituion: bool,
+
+	// Should we print simple powers
+	// as unicode superscript chars?
+	//
+	// Automatically disables if enable_unicode is off.
+	pub enable_super_powers: bool,
+
+	// Should we write "one-over" fractions
+	// as -1 powers?
+	//
+	// Automatically disabled if enable_super_powers is off.
+	pub enable_one_over_power: bool,
+}
+
+impl Config {
+	pub fn new() -> Config {
+		Config{
+			term_color_type: 2,
+			//enable_substituion: true,
+			//enable_unicode: true,
+			enable_super_powers: true,
+			enable_one_over_power: true
+		}
+	}
+
+	pub fn check(&mut self) {
+		//if !self.enable_unicode {
+		//	self.enable_substituion = false;
+		//	self.enable_super_powers = false;
+		//}
+
+		if !self.enable_super_powers {
+			self.enable_one_over_power = false
+		}
+	}
+}
+
+
+
+
+#[derive(Debug)]
+#[derive(Clone)]
 pub struct Context {
+	pub config: Config,
+
 	history: Vec<Expression>,
 	variables: HashMap<String, Expression>,
 	functions: HashMap<String, (Vec<String>, Expression)>,
@@ -16,6 +77,7 @@ pub struct Context {
 impl Context {
 	pub fn new() -> Context {
 		Context{
+			config: Config::new(),
 			history: Vec::new(),
 			variables: HashMap::new(),
 			functions: HashMap::new(),

src/entrypoint/unix/unix.rs

@@ -1,4 +1,3 @@
-use std::io::Write;
 use std::io::stdout;
 use std::io::stdin;
 use std::env;
@@ -6,19 +5,33 @@ use std::env;
 use termion::{
 	event::Key,
 	input::TermRead,
-	raw::IntoRawMode
+	raw::IntoRawMode,
+	color::DetectColors
 };
 
 use super::promptbuffer::PromptBuffer;
 use crate::command;
 use crate::context::Context;
-
+use crate::FormattedText;
 
 #[inline(always)]
 pub fn main() -> Result<(), std::io::Error> {
 	let mut stdout = stdout().into_raw_mode().unwrap();
 	let mut pb: PromptBuffer = PromptBuffer::new(64);
-	let mut context: Context = Context::new();
+	let mut context = Context::new();
+
+	// Set color compatibilty
+	let term_colors = stdout.available_colors().unwrap_or(0);
+	if term_colors >= 256 {
+		context.config.term_color_type = 2
+	} else if term_colors >= 8 {
+		context.config.term_color_type = 1
+	} else {
+		context.config.term_color_type = 0
+	}
+
+	context.config.check();
+
 
 
 	// Handle command-line arguments
@@ -28,7 +41,21 @@ pub fn main() -> Result<(), std::io::Error> {
 		t.write(&context, &mut stdout)?;
 		return Ok(());
 	} else if args.iter().any(|s| s == "--version") {
-		write!(stdout, "Daisy v{}\r\n", env!("CARGO_PKG_VERSION"))?;
+		let t = FormattedText::new(format!(
+			"Daisy v{}\n", env!("CARGO_PKG_VERSION")
+		));
+		t.write(&context, &mut stdout)?;
+		return Ok(());
+	} else if args.iter().any(|s| s == "--debug") {
+		let t = FormattedText::new(format!(
+			concat!(
+				"Daisy v{}\n",
+				"Your terminal supports {} colors.\n"
+			),
+			env!("CARGO_PKG_VERSION"),
+			term_colors
+		));
+		t.write(&context, &mut stdout)?;
 		return Ok(());
 	}
 
@@ -45,7 +72,7 @@ pub fn main() -> Result<(), std::io::Error> {
 						// while inside a substitution
 						pb.write_prompt_nocursor(&mut context, &mut stdout)?;
 						let in_str = pb.enter();
-						write!(stdout, "\r\n")?;
+						FormattedText::newline(&mut stdout)?;
 						if in_str == "" { break; }
 
 						if in_str.trim() == "quit" {
@@ -83,6 +110,6 @@ pub fn main() -> Result<(), std::io::Error> {
 		}
 	}
 
-	write!(stdout, "\r\n")?;
+	FormattedText::newline(&mut stdout)?;
 	return Ok(());
 }

src/evaluate/operator.rs

@@ -78,8 +78,8 @@ pub fn eval_operator(context: &mut Context, g: &Expression) -> Result<Option<Exp
 						return Err((
 							*la + *lb + *op_loc,
 							DaisyError::IncompatibleUnits(
-								a.convert_to_base().unit.to_string(),
+								a.convert_to_base().unit.display(context),
-								b.convert_to_base().unit.to_string()
+								b.convert_to_base().unit.display(context)
 							)
 						));
 					}
@@ -101,8 +101,8 @@ pub fn eval_operator(context: &mut Context, g: &Expression) -> Result<Option<Exp
 						return Err((
 							*la + *lb + *op_loc,
 							DaisyError::IncompatibleUnits(
-								a.convert_to_base().unit.to_string(),
+								a.convert_to_base().unit.display(context),
-								b.convert_to_base().unit.to_string()
+								b.convert_to_base().unit.display(context)
 							)
 						));
 					}
@@ -179,8 +179,8 @@ pub fn eval_operator(context: &mut Context, g: &Expression) -> Result<Option<Exp
 						return Err((
 							*la + *lb + *op_loc,
 							DaisyError::IncompatibleUnits(
-								va.convert_to_base().unit.to_string(),
+								va.convert_to_base().unit.display(context),
-								vb.convert_to_base().unit.to_string()
+								vb.convert_to_base().unit.display(context)
 							)
 						));
 					}

src/formattedtext.rs

@@ -5,6 +5,7 @@ use termion::style;
 use termion::clear;
 use termion::cursor;
 use std::ops::Add;
+use crate::context::Context;
 
 
 #[derive(Debug)]
@@ -18,8 +19,92 @@ impl ToString for FormattedText {
 }
 
 
-impl FormattedText {
+fn format_map_none(c: char) -> Option<String> {
+	Some(match c {
+		'n'|'i'|'t'|'a'|
+		'e'|'c'|'s'|'r'
+		=> { "".to_string() },
+		_ => { return None }
+	})
+}
 
+
+fn format_map_ansi(c: char) -> Option<String> {
+	Some(match c {
+		'n' => { // Normal text
+			format!("{}{}", color::Fg(color::Reset), color::Bg(color::Reset))
+		},
+		'i' => { // Normal italic text
+			format!("{}{}", color::Fg(color::Reset), color::Bg(color::Reset))
+		},
+		't' => { // Title text
+			format!("{}{}", color::Fg(color::AnsiValue(6)), color::Bg(color::Reset))
+		},
+		'a' => { // Colored text
+			format!("{}{}", color::Fg(color::AnsiValue(5)), color::Bg(color::Reset))
+		},
+		'e' => { // Error titles
+			format!("{}{}", color::Fg(color::AnsiValue(1)), color::Bg(color::Reset))
+		},
+		'c' => { // Console text
+			format!("{}{}", color::Fg(color::AnsiValue(0)), color::Bg(color::AnsiValue(7)))
+		},
+		's' => { // Repeat prompt (how => is styled)
+			format!("{}{}", color::Fg(color::AnsiValue(2)), color::Bg(color::Reset))
+		},
+		'r' => { // Result prompt (how = is styled)
+			format!("{}{}", color::Fg(color::AnsiValue(4)), color::Bg(color::Reset))
+		},
+
+		_ => { return None }
+	})
+}
+
+
+fn format_map_full(c: char) -> Option<String> {
+	Some(match c {
+		'n' => { // Normal text
+			format!("{}{}", color::Fg(color::Reset), style::Reset)
+		},
+		'i' => { // Normal italic text
+			format!("{}{}", color::Fg(color::Reset), style::Italic)
+		},
+		't' => { // Title text
+			format!("{}{}", color::Fg(color::Magenta), style::Bold)
+		},
+		'a' => { // Colored text
+			format!("{}{}", color::Fg(color::Magenta), style::Reset)
+		},
+		'e' => { // Error titles
+			format!("{}{}", color::Fg(color::Red), style::Bold)
+		},
+		'c' => { // Console text
+			format!("{}{}", color::Fg(color::LightBlack), style::Italic)
+		},
+		's' => { // Repeat prompt (how => is styled)
+			format!("{}{}", color::Fg(color::Magenta), style::Bold)
+		},
+		'r' => { // Result prompt (how = is styled)
+			format!("{}{}", color::Fg(color::Green), style::Bold)
+		},
+
+		_ => { return None }
+	})
+}
+
+
+impl FormattedText {
+	pub fn newline(stdout: &mut RawTerminal<std::io::Stdout>) -> Result<(), std::io::Error> {
+		write!(
+			stdout,
+			"\r\n",
+		)?;
+		return Ok(());
+	}
+}
+
+
+impl FormattedText {
 	pub fn new(s: String) -> FormattedText {
 		return FormattedText {
 			text: s
@@ -58,30 +143,22 @@ impl FormattedText {
 					let b = chars.next().unwrap();
 
 					match (a, b) {
-						('n', ']') => { // Normal text
+						(c, ']') => { // Normal text
-							s.push_str(&format!("{}{}", color::Fg(color::Reset), style::Reset));
-						},
-						('i', ']') => { // Normal italic text
-							s.push_str(&format!("{}{}", color::Fg(color::Reset), style::Italic));
-						},
-						('t', ']') => { // Title text
-							s.push_str(&format!("{}{}", color::Fg(color::Magenta), style::Bold));
-						},
-						('a', ']') => { // Colored text
-							s.push_str(&format!("{}{}", color::Fg(color::Magenta), style::Reset));
-						},
-						('e', ']') => { // Error titles
-							s.push_str(&format!("{}{}", color::Fg(color::Red), style::Bold));
-						},
-						('c', ']') => { // Console text
-							s.push_str(&format!("{}{}", color::Fg(color::LightBlack), style::Italic));
-						},
 
-						('s', ']') => { // Repeat prompt (how => is styled)
+							let q = match context.config.term_color_type {
-							s.push_str(&format!("{}{}", color::Fg(color::Magenta), style::Bold));
+								0 => format_map_none(c),
-						},
+								1 => format_map_ansi(c),
-						('r', ']') => { // Result prompt (how = is styled)
+								2 => format_map_full(c),
-							s.push_str(&format!("{}{}", color::Fg(color::Green), style::Bold));
+								_ => unreachable!("Invalid term_color_type")
+							};
+
+							if q.is_some() {
+								s.push_str(&q.unwrap());
+							} else {
+								s.push('[');
+								s.push(a);
+								s.push(b);
+							}
 						},
 
 						_ => {

src/main.rs

@@ -85,13 +85,13 @@ fn do_expression(
 	// Display parsed string
 	output.push(&format!(
 		" [s]=>[n] {}\n\n",
-		g.to_string()
+		g.display(context)
 	));
 
 	// Display result
 	output.push(&format!(
 		"  [r]=[n] {}\n\n",
-		g_evaluated.to_string_outer(),
+		g_evaluated.display_outer(context),
 	));
 
 	return Ok((output, g_evaluated));
@@ -224,7 +224,7 @@ fn do_assignment(
 		// Display parsed string
 		output.push(&format!(
 			" [s]=>[n] {left} = {}\n\n",
-			g.to_string()
+			g.display(context)
 		));
 
 		// Evaluate expression with shadow variables
@@ -266,7 +266,7 @@ fn do_assignment(
 		// Display parsed string
 		output.push(&format!(
 			" [t]=>[n] {left} = {}\n\n",
-			g.to_string()
+			g.display(context)
 		));
 
 		// Evaluate expression

src/parser/expression/expression.rs

@@ -1,5 +1,6 @@
 use std::collections::VecDeque;
 use crate::quantity::Quantity;
+use crate::context::Context;
 
 use super::Operator;
 use super::Constant;
@@ -17,17 +18,17 @@ pub enum Expression {
 	Tuple(LineLocation, VecDeque<Expression>),
 }
 
-impl ToString for Expression {
+impl Expression {
-	fn to_string(&self) -> String {
+	pub fn display(&self, context: &Context) -> String {
 		match self {
-			Expression::Quantity(_, v) => v.to_string(),
+			Expression::Quantity(_, v) => v.display(context),
 			Expression::Constant(_, c) => c.to_string(),
 			Expression::Variable(_, s) => s.clone(),
-			Expression::Operator(_, o,a) => o.print(a),
+			Expression::Operator(_, o,a) => o.display(context, a),
 			Expression::Tuple(_, v) => {
 				format!("({})",
 					v.iter()
-						.map(|x| x.to_string())
+						.map(|x| x.display(context))
 						.collect::<Vec<String>>()
 						.join(", ")
 				)
@@ -39,16 +40,16 @@ impl ToString for Expression {
 impl Expression {
 	// This is called only when this is the outermost Expression.
 	// This sometimes leads to different--usually more verbose--behavior.
-	pub fn to_string_outer(&self) -> String {
+	pub fn display_outer(&self, context: &Context) -> String {
 		match self {
-			Expression::Quantity(_, v) => v.to_string_outer(),
+			Expression::Quantity(_, v) => v.display_outer(context),
 			Expression::Constant(_, c) => c.to_string(),
 			Expression::Variable(_, s) => s.clone(),
-			Expression::Operator(_, o,a) => o.print(a),
+			Expression::Operator(_, o,a) => o.display(context, a),
 			Expression::Tuple(_, v) => {
 				format!("({})",
 					v.iter()
-						.map(|x| x.to_string())
+						.map(|x| x.display(context))
 						.collect::<Vec<String>>()
 						.join(", ")
 				)

src/parser/expression/operator.rs

@@ -128,8 +128,8 @@ impl Operator {
 	}
 
 	#[inline(always)]
-	fn add_parens_to_arg(&self, arg: &Expression) -> String {
+	fn add_parens_to_arg(&self, context: &Context, arg: &Expression) -> String {
-		let mut astr: String = arg.to_string();
+		let mut astr: String = arg.display(context);
 		if let Expression::Operator(_, o,_) = arg {
 			if o.print_map() < self.print_map() {
 				astr = format!("({})", astr);
@@ -139,8 +139,8 @@ impl Operator {
 	}
 
 	#[inline(always)]
-	fn add_parens_to_arg_strict(&self, arg: &Expression) -> String {
+	fn add_parens_to_arg_strict(&self, context: &Context, arg: &Expression) -> String {
-		let mut astr: String = arg.to_string();
+		let mut astr: String = arg.display(context);
 		if let Expression::Operator(_, o,_) = arg {
 			if o.print_map() <= self.print_map() {
 				astr = format!("({})", astr);
@@ -150,56 +150,56 @@ impl Operator {
 	}
 
 
-	pub fn print(&self, args: &VecDeque<Expression>) -> String {
+	pub fn display(&self, context: &Context, args: &VecDeque<Expression>) -> String {
 		match self {
 			Operator::Negative => {
-				return format!("-{}", self.add_parens_to_arg(&args[0]));
+				return format!("-{}", self.add_parens_to_arg(context, &args[0]));
 			},
 
 			Operator::Sqrt => {
 				return format!(
 					"√{}",
-					self.add_parens_to_arg(&args[0]),
+					self.add_parens_to_arg(context, &args[0]),
 				);
 			},
 
 			Operator::ModuloLong => {
 				return format!(
 					"{} mod {}",
-					self.add_parens_to_arg(&args[0]),
+					self.add_parens_to_arg(context, &args[0]),
-					self.add_parens_to_arg(&args[1])
+					self.add_parens_to_arg(context, &args[1])
 				);
 			},
 
 			Operator::DivideLong => {
 				return format!(
 					"{} per {}",
-					self.add_parens_to_arg(&args[0]),
+					self.add_parens_to_arg(context, &args[0]),
-					self.add_parens_to_arg(&args[1])
+					self.add_parens_to_arg(context, &args[1])
 				);
 			},
 
 			Operator::UnitConvert => {
 				return format!(
 					"{} to {}",
-					self.add_parens_to_arg(&args[0]),
+					self.add_parens_to_arg(context, &args[0]),
-					self.add_parens_to_arg(&args[1])
+					self.add_parens_to_arg(context, &args[1])
 				);
 			},
 
 			Operator::Modulo => {
 				return format!(
 					"{} % {}",
-					self.add_parens_to_arg(&args[0]),
+					self.add_parens_to_arg(context, &args[0]),
-					self.add_parens_to_arg(&args[1])
+					self.add_parens_to_arg(context, &args[1])
 				);
 			},
 
 			Operator::Subtract => {
 				return format!(
 					"{} - {}",
-					self.add_parens_to_arg(&args[0]),
+					self.add_parens_to_arg(context, &args[0]),
-					self.add_parens_to_arg(&args[1])
+					self.add_parens_to_arg(context, &args[1])
 				);
 			},
 
@@ -208,13 +208,13 @@ impl Operator {
 				let q = &args[1];
 
 				if {
-					//context.config.enable_super_powers &&
+					context.config.enable_super_powers &&
 					q.is_unitless_integer() &&
-					!q.to_string().contains("e")
+					!q.display(context).contains("e")
 				} {
 					// Write integer powers as a superscript
 					let mut b = String::new();
-					for c in q.to_string().chars() {
+					for c in q.display(context).chars() {
 						b.push(match c {
 							'-' => '⁻',
 							'0' => '⁰',
@@ -233,27 +233,27 @@ impl Operator {
 
 					return format!(
 						"{}{}",
-						self.add_parens_to_arg_strict(&args[0]),
+						self.add_parens_to_arg_strict(context, &args[0]),
 						b
 					);
 				} else {
 					return format!(
 						"{}^{}",
-						self.add_parens_to_arg_strict(&args[0]),
+						self.add_parens_to_arg_strict(context, &args[0]),
-						self.add_parens_to_arg_strict(&args[1])
+						self.add_parens_to_arg_strict(context, &args[1])
 					);
 				}
 			},
 
 			Operator::Factorial => {
-				return format!("{}!", self.add_parens_to_arg(&args[0]));
+				return format!("{}!", self.add_parens_to_arg(context, &args[0]));
 			},
 
 			Operator::Add => {
 				return format!(
 					"{} + {}",
-					self.add_parens_to_arg(&args[0]),
+					self.add_parens_to_arg(context, &args[0]),
-					self.add_parens_to_arg(&args[1])
+					self.add_parens_to_arg(context, &args[1])
 				);
 			},
 
@@ -283,26 +283,26 @@ impl Operator {
 					if let Expression::Quantity(_, u) = b {
 						if u.unit.no_space() {
 							return format!("{}{}",
-								self.add_parens_to_arg_strict(a),
+								self.add_parens_to_arg_strict(context, a),
-								self.add_parens_to_arg_strict(b)
+								self.add_parens_to_arg_strict(context, b)
 							);
 						} else {
 							return format!("{} {}",
-								self.add_parens_to_arg_strict(a),
+								self.add_parens_to_arg_strict(context, a),
-								self.add_parens_to_arg_strict(b)
+								self.add_parens_to_arg_strict(context, b)
 							);
 						}
 					} else {
 						return format!("{}{}",
-							self.add_parens_to_arg_strict(a),
+							self.add_parens_to_arg_strict(context, a),
-							self.add_parens_to_arg_strict(b)
+							self.add_parens_to_arg_strict(context, b)
 						);
 					};
 
 				} else {
 					return format!("{} × {}",
-						self.add_parens_to_arg_strict(a),
+						self.add_parens_to_arg_strict(context, a),
-						self.add_parens_to_arg_strict(b)
+						self.add_parens_to_arg_strict(context, b)
 					);
 				}
 			},
@@ -313,25 +313,25 @@ impl Operator {
 
 
 				if let Expression::Quantity(_, q) = a {
-					if q.is_one() {
+					if q.is_one() && context.config.enable_one_over_power {
 						return format!("{}⁻¹",
-							self.add_parens_to_arg_strict(b)
+							self.add_parens_to_arg_strict(context, b)
 						);
 					}
 				}
 
 				return format!("{} ÷ {}",
-					self.add_parens_to_arg_strict(a),
+					self.add_parens_to_arg_strict(context, a),
-					self.add_parens_to_arg_strict(b)
+					self.add_parens_to_arg_strict(context, b)
 				);
 			},
 
 			Operator::Function(s) => {
-				return format!("{}({})", s.to_string(), args[0].to_string());
+				return format!("{}({})", s.to_string(), args[0].display(context));
 			},
 
 			Operator::UserFunction(s) => {
-				return format!("{}({})", s.to_string(), args[0].to_string());
+				return format!("{}({})", s, args[0].display(context));
 			}
 		};
 	}

src/quantity/quantity.rs

@@ -7,6 +7,7 @@ use std::ops::{
 };
 use std::cmp::Ordering;
 
+use crate::context::Context;
 use crate::quantity::Unit;
 use crate::quantity::FreeUnit;
 
@@ -21,12 +22,12 @@ pub struct Quantity {
 
 
 
-impl ToString for Quantity {
+impl Quantity {
-	fn to_string(&self) -> String {
+	pub fn display(&self, context: &Context) -> String {
 		let n = self.scalar.to_string();
 		if self.unitless() { return n; }
 
-		let u = self.unit.to_string();
+		let u = self.unit.display(context);
 		if self.is_one() { return u; };
 
 		if self.unit.no_space() {
@@ -38,11 +39,11 @@ impl ToString for Quantity {
 }
 
 impl Quantity {
-	pub fn to_string_outer(&self) -> String {
+	pub fn display_outer(&self, context: &Context) -> String {
 		let n = self.scalar.to_string();
 		if self.unitless() { return n; }
 
-		let u = self.unit.to_string();
+		let u = self.unit.display(context);
 		if self.unit.no_space() {
 			return format!("{n}{u}");
 		} else {

src/quantity/unit/unit.rs

@@ -4,6 +4,7 @@ use std::ops::{
 	MulAssign, DivAssign
 };
 
+use crate::context::Context;
 use crate::quantity::Scalar;
 use crate::quantity::Quantity;
 use super::FreeUnit;
@@ -16,8 +17,8 @@ pub struct Unit {
 	pub val: HashMap<FreeUnit, Scalar>
 }
 
-impl ToString for Unit {
+impl Unit {
-	fn to_string(&self) -> String {
+	pub fn display(&self, context: &Context) -> String {
 
 		if self.unitless() { return String::new(); };
 
@@ -37,7 +38,11 @@ impl ToString for Unit {
 
 			if *p == Scalar::new_rational(1f64).unwrap() {
 				t.push_str(&format!("{c}·"));
-			} else if p.is_int() && !p.to_string().contains("e"){
+			} else if {
+				context.config.enable_super_powers &&
+				p.is_int() &&
+				!p.to_string().contains("e")
+			} {
 				t.push_str(&c);
 				for c in p.to_string().chars() {
 					t.push( match c {
@@ -74,7 +79,11 @@ impl ToString for Unit {
 			bottom_count += 1;
 			if t.len() != 0 && *p == Scalar::new_rational(-1f64).unwrap() {
 				b.push_str(&format!("{c}·"));
-			} else if p.is_int() && !p.to_string().contains("e") {
+			} else if {
+				context.config.enable_super_powers &&
+				p.is_int() &&
+				!p.to_string().contains("e")
+			} {
 				b.push_str(&c);
 				for c in p.to_string().chars() {
 					if c == '-' && t.len() != 0 { continue; }

src/tests.rs

@@ -10,8 +10,10 @@ fn eval_to_str(s: &str) -> Result<String, ()> {
 	};
 	//let out_str = g.print();
 
-	return match evaluate(&mut Context::new(), &g) {
+	let mut c = Context::new();
-		Ok(x) => Ok(x.to_string_outer()),
+
+	return match evaluate(&mut c, &g) {
+		Ok(x) => Ok(x.display_outer(&c)),
 		Err(_) => Err(())
 	};
 }