From 853312ce67703fb38c10c176ae4de42d75994930 Mon Sep 17 00:00:00 2001
From: Eryn Wells <eryn@erynwells.me>
Date: Mon, 3 Sep 2018 17:17:49 -0700
Subject: [PATCH] [lexer] We can lex integers!

---
 lexer/src/states/begin.rs        | 22 +++++++++++++++-------
 lexer/src/states/hash.rs         |  2 +-
 lexer/src/states/number/digit.rs |  4 +---
 lexer/src/states/number/mod.rs   | 10 +++++++---
 4 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/lexer/src/states/begin.rs b/lexer/src/states/begin.rs
index 670b0dc..d8770ee 100644
--- a/lexer/src/states/begin.rs
+++ b/lexer/src/states/begin.rs
@@ -8,20 +8,28 @@ use token::Token;
 use states::{Resume, State, StateResult};
 use states::id::IdSub;
 use states::hash::Hash;
+use states::number::{Builder, Digit};
 
 #[derive(Debug)]
 pub struct Begin;
 
 impl State for Begin {
     fn lex(&mut self, c: char) -> StateResult {
-        match c {
-            c if c.is_left_paren() => StateResult::Emit(Token::LeftParen, Resume::AtNext),
-            c if c.is_right_paren() => StateResult::Emit(Token::RightParen, Resume::AtNext),
+        if c.is_left_paren() {
+            StateResult::Emit(Token::LeftParen, Resume::AtNext)
+        } else if c.is_right_paren() {
+            StateResult::Emit(Token::RightParen, Resume::AtNext)
+        } else if c.is_whitespace() {
             // TODO: Figure out some way to track newlines.
-            c if c.is_whitespace() => StateResult::Continue,
-            c if c.is_identifier_initial() => StateResult::Advance { to: Box::new(IdSub{}) },
-            c if c.is_hash() => StateResult::Advance { to: Box::new(Hash::new()) },
-            _ => StateResult::fail(Error::invalid_char(c)),
+            StateResult::Continue
+        } else if c.is_identifier_initial() {
+            StateResult::advance(Box::new(IdSub{}))
+        } else if c.is_hash() {
+            StateResult::advance(Box::new(Hash::new()))
+        } else if let Some(st) = Digit::with_char(Builder::new(), c) {
+            StateResult::advance(Box::new(st))
+        } else {
+            StateResult::fail(Error::invalid_char(c))
         }
     }
 
diff --git a/lexer/src/states/hash.rs b/lexer/src/states/hash.rs
index ffccbb5..80f7103 100644
--- a/lexer/src/states/hash.rs
+++ b/lexer/src/states/hash.rs
@@ -39,7 +39,7 @@ impl State for Hash {
     }
 
     fn none(&mut self) -> Result<Option<Token>, Error> {
-        Ok(None)
+        Err(Error::unexpected_eof())
     }
 }
 
diff --git a/lexer/src/states/number/digit.rs b/lexer/src/states/number/digit.rs
index d571cbb..fb5ccef 100644
--- a/lexer/src/states/number/digit.rs
+++ b/lexer/src/states/number/digit.rs
@@ -2,11 +2,9 @@
  * Eryn Wells <eryn@erynwells.me>
  */
 
-use chars::Lexable;
 use error::Error;
 use states::{State, StateResult};
 use states::number::{Builder, Radix, Exact};
-use states::number::sign::Sign;
 use token::Token;
 
 #[derive(Debug)] pub struct Digit(Builder);
@@ -39,6 +37,6 @@ impl State for Digit {
     }
 
     fn none(&mut self) -> Result<Option<Token>, Error> {
-        Err(Error::unexpected_eof())
+        Ok(Some(Token::Num(self.0.resolve())))
     }
 }
diff --git a/lexer/src/states/number/mod.rs b/lexer/src/states/number/mod.rs
index daeecde..c0612a7 100644
--- a/lexer/src/states/number/mod.rs
+++ b/lexer/src/states/number/mod.rs
@@ -9,6 +9,7 @@ mod prefix;
 mod sign;
 
 pub use self::prefix::Prefix;
+pub use self::digit::Digit;
 
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 pub enum Radix { Bin = 2, Oct = 8, Dec = 10, Hex = 16 }
@@ -83,9 +84,12 @@ impl Builder {
     }
 
     fn resolve(&self) -> i64 {
-        //let sign_factor: i64 = if let Some(sign) = self.sign { sign as i64 } else { 1 };
-        //self.value * sign_factor
-        0
+        let sign_factor: i64 = if let Some(sign) = self.sign {
+            sign as i64
+        } else {
+            1
+        };
+        self.value * sign_factor
     }
 
     fn seen_exact(&self) -> bool { self.exact.is_some() }