Add exactness indicator

This commit is contained in:
Eryn Wells 2016-12-27 10:08:44 -07:00
parent 9ac596187d
commit 00d8380eac
2 changed files with 142 additions and 9 deletions

View file

@ -9,6 +9,7 @@ mod number;
mod str;
use self::char::Lexable;
use self::number::Exactness;
use self::number::NumberBuilder;
use self::number::Radix;
use self::number::Sign;
@ -25,7 +26,11 @@ enum State {
Dot,
Hash,
Number,
NumberExactness,
NumberDecimal,
NumberRadix,
NumberSign,
Sign,
String,
}
@ -112,7 +117,10 @@ impl Lexer {
}
else if let Some(sign) = Sign::from_char(c) {
*token = Some(Token::Identifier(c.to_string()));
self.number_builder = NumberBuilder::new();
self.number_builder.sign(sign);
self.state = State::Sign;
self.advance();
}
else if c.is_identifier_initial() {
self.state = State::Identifier;
@ -146,7 +154,7 @@ impl Lexer {
/// Handle self.state == State::Identifier
fn state_identifier(&mut self, c: char, token: &mut Option<Token>) {
if c.is_identifier_subsequent() {
// State in Identifier state.
// Stay in Identifier state.
self.advance();
}
else if c.is_identifier_delimiter() {
@ -176,12 +184,22 @@ impl Lexer {
fn state_hash(&mut self, c: char, token: &mut Option<Token>) {
if c.is_boolean_true() || c.is_boolean_false() {
self.advance();
*token = Some(Token::Boolean(c.is_boolean_true()));
self.advance();
}
else if c.is_left_paren() {
self.advance();
*token = Some(Token::LeftVectorParen);
self.advance();
}
else if let Some(radix) = Radix::from_char(c) {
self.number_builder.radix(radix);
self.state = State::NumberRadix;
self.advance();
}
else if let Some(exactness) = Exactness::from_char(c) {
self.number_builder.exact(exactness);
self.state = State::NumberExactness;
self.advance();
}
else {
assert!(false, "Invalid token character: '{}'", c);
@ -206,6 +224,21 @@ impl Lexer {
}
}
fn state_number_exactness(&mut self, c: char, token: &mut Option<Token>) {
if c.is_hash() {
self.state = State::Hash;
self.advance();
}
else if c.is_digit(self.number_builder.radix_value()) {
self.number_builder.extend_value(c);
self.state = State::Number;
self.advance();
}
else {
assert!(false, "Invalid token character: '{}'", c);
}
}
fn state_number_decimal(&mut self, c: char, token: &mut Option<Token>) {
if c.is_digit(Radix::Dec.value()) {
self.number_builder.extend_decimal_value(c);
@ -220,6 +253,60 @@ impl Lexer {
}
}
fn state_number_radix(&mut self, c: char, token: &mut Option<Token>) {
if c.is_digit(self.number_builder.radix_value()) {
self.number_builder.extend_value(c);
self.state = State::Number;
self.advance();
}
else if c.is_dot() {
self.state = State::NumberDecimal;
self.advance();
}
else if c.is_hash() {
self.state = State::Hash;
self.advance();
}
else if let Some(sign) = Sign::from_char(c) {
self.number_builder.sign(sign);
self.state = State::NumberSign;
self.advance();
}
else {
assert!(false, "Invalid token character: '{}'", c);
}
}
fn state_number_sign(&mut self, c: char, token: &mut Option<Token>) {
if c.is_digit(self.number_builder.radix_value()) {
self.number_builder.extend_value(c);
self.state = State::Number;
self.advance();
}
else if c.is_dot() {
self.state = State::NumberDecimal;
self.advance();
}
else {
assert!(false, "Invalid token character: '{}'", c);
}
}
fn state_sign(&mut self, c: char, token: &mut Option<Token>) {
if c.is_digit(Radix::Dec.value()) {
self.number_builder.extend_value(c);
self.state = State::Number;
self.advance();
}
else if c.is_identifier_delimiter() {
*token = Some(Token::Identifier(self.value()));
self.retract();
}
else {
assert!(false, "Invalid token character: '{}'", c);
}
}
fn state_string(&mut self, c: char, token: &mut Option<Token>) {
self.advance();
if c.is_string_quote() {
@ -263,7 +350,11 @@ impl Iterator for Lexer {
State::Dot => self.state_dot(c, &mut token),
State::Hash => self.state_hash(c, &mut token),
State::Number => self.state_number(c, &mut token),
State::NumberExactness => self.state_number_exactness(c, &mut token),
State::NumberDecimal => self.state_number_decimal(c, &mut token),
State::NumberRadix => self.state_number_radix(c, &mut token),
State::NumberSign => self.state_number_sign(c, &mut token),
State::Sign => self.state_sign(c, &mut token),
State::String => self.state_string(c, &mut token),
State::Comment => self.state_comment(c, &mut token),
}
@ -331,12 +422,41 @@ mod tests {
}
#[test]
fn lexer_finds_numbers() {
check_single_token("34", Token::Number(Number::new(34.0)));
fn finds_numbers() {
check_single_token(".34", Token::Number(Number::new(0.34)));
check_single_token("0.34", Token::Number(Number::new(0.34)));
}
#[test]
fn finds_negative_numbers() {
check_single_token("-3", Token::Number(Number::from_int(-3)));
check_single_token("-0", Token::Number(Number::from_int(-0)));
check_single_token("-0.56", Token::Number(Number::new(-0.56)));
check_single_token("-3.14159", Token::Number(Number::new(-3.14159)));
}
#[test]
fn finds_bin_numbers() {
check_single_token("#b0", Token::Number(Number::from_int(0b0)));
check_single_token("#b01011", Token::Number(Number::from_int(0b01011)));
}
#[test]
fn finds_dec_numbers() {
check_single_token("34", Token::Number(Number::new(34.0)));
check_single_token("#d89", Token::Number(Number::from_int(89)));
}
#[test]
fn finds_oct_numbers() {
check_single_token("#o45", Token::Number(Number::from_int(0o45)));
}
#[test]
fn finds_hex_numbers() {
check_single_token("#h4A65", Token::Number(Number::from_int(0x4A65)));
}
fn check_single_token(input: &str, expected: Token) {
let mut lexer = Lexer::new(input);
assert_next_token(&mut lexer, &expected);

View file

@ -21,9 +21,12 @@ pub enum Radix { Bin, Oct, Dec, Hex }
#[derive(PartialEq, Debug)]
pub enum Sign { Pos, Neg }
#[derive(PartialEq, Debug)]
pub enum Exactness { Exact, Inexact }
#[derive(Debug)]
pub struct NumberBuilder {
exact: bool,
exact: Exactness,
radix: Radix,
sign: Sign,
value: f64,
@ -33,7 +36,7 @@ pub struct NumberBuilder {
impl NumberBuilder {
pub fn new() -> NumberBuilder {
NumberBuilder {
exact: false,
exact: Exactness::Inexact,
radix: Radix::Dec,
sign: Sign::Pos,
value: 0.0,
@ -41,7 +44,7 @@ impl NumberBuilder {
}
}
pub fn exact<'a>(&'a mut self, ex: bool) -> &'a mut NumberBuilder {
pub fn exact<'a>(&'a mut self, ex: Exactness) -> &'a mut NumberBuilder {
self.exact = ex;
self
}
@ -129,6 +132,16 @@ impl Sign {
}
}
impl Exactness {
pub fn from_char(c: char) -> Option<Exactness> {
match c {
'i' => Some(Exactness::Inexact),
'e' => Some(Exactness::Exact),
_ => None,
}
}
}
#[cfg(test)]
mod tests {
use super::*;