[lexer] Move Bool state to its own file

lexer/src/states/bool.rs

@@ -0,0 +1,68 @@
+/* lexer/src/states/bool.rs
+ * Eryn Wells <eryn@erynwells.me>
+ */
+
+use chars::Lexable;
+use states::{Resume, State, StateResult};
+use token::Token;
+
+const TRUE_SHORT: &'static str = "t";
+const TRUE: &'static str = "true";
+const FALSE_SHORT: &'static str = "f";
+const FALSE: &'static str = "false";
+
+#[derive(Debug)] pub struct Bool(String);
+
+impl Bool {
+    pub fn new(buf: &str) -> Bool {
+        Bool(buf.to_string())
+    }
+
+    fn handle_delimiter(&self) -> Option<Token> {
+        if self.0 == TRUE || self.0 == TRUE_SHORT {
+            Some(Token::Bool(true))
+        } else if self.0 == FALSE || self.0 == FALSE_SHORT {
+            Some(Token::Bool(false))
+        } else {
+            None
+        }
+    }
+}
+
+impl State for Bool {
+    fn lex(&mut self, c: char) -> StateResult {
+        match c {
+            c if c.is_identifier_delimiter() => match self.handle_delimiter() {
+                Some(token) => StateResult::Emit(token, Resume::Here),
+                None => {
+                    let msg = format!("Invalid character: {}", c);
+                    StateResult::fail(msg.as_str())
+                },
+            },
+            _ => {
+                let buf = {
+                    let mut b = String::from(self.0.as_str());
+                    b.push(c);
+                    b
+                };
+                if TRUE.starts_with(&buf) || FALSE.starts_with(&buf) {
+                    StateResult::advance(Box::new(Bool(buf)))
+                } else {
+                    let msg = format!("Invalid character: {}", c);
+                    StateResult::fail(msg.as_str())
+                }
+            },
+        }
+    }
+
+    fn none(&mut self) -> Result<Option<Token>, String> {
+        match self.handle_delimiter() {
+            Some(token) => Ok(Some(token)),
+            None => {
+                let msg = format!("Found EOF while trying to parse a bool");
+                Err(msg)
+            }
+        }
+    }
+}
+

lexer/src/states/hash.rs

@@ -2,19 +2,16 @@
  * Eryn Wells <eryn@erynwells.me>
  */
 
-//! Lexer states for handling tokens that begin with hash marks '#'.
-
-use chars::Lexable;
-use states::{Resume, State, StateResult};
+use states::{State, StateResult};
+use states::bool::Bool;
 use token::Token;
 
-const TRUE_SHORT: &'static str = "t";
-const TRUE: &'static str = "true";
-const FALSE_SHORT: &'static str = "f";
-const FALSE: &'static str = "false";
+trait HashLexable {
+    fn is_bool_initial(&self) -> bool;
+    fn is_slash(&self) -> bool;
+}
 
 #[derive(Debug)] pub struct Hash;
-#[derive(Debug)] pub struct BoolSub(String);
 
 impl Hash {
     pub fn new() -> Hash { Hash{} }
@@ -23,14 +20,14 @@ impl Hash {
 impl State for Hash {
     fn lex(&mut self, c: char) -> StateResult {
         match c {
-            c if TRUE.starts_with(c) || FALSE.starts_with(c) => {
-                let buf = c.to_lowercase().to_string();
-                StateResult::Advance { to: Box::new(BoolSub(buf)) }
-            }
+            c if c.is_bool_initial() => {
+                let buf = c.to_ascii_lowercase().to_string();
+                StateResult::advance(Box::new(Bool::new(buf.as_str())))
+            },
             _ => {
                 let msg = format!("Invalid character: {}", c);
-                StateResult::Fail { msg }
-            }
+                StateResult::fail(msg.as_str())
+            },
         }
     }
 
@@ -39,61 +36,7 @@ impl State for Hash {
     }
 }
 
-impl BoolSub {
-    fn handle_delimiter(&self) -> Result<(Token, Resume), ()> {
-        if self.0 == TRUE || self.0 == TRUE_SHORT {
-            Ok((Token::Bool(true), Resume::Here))
-        } else if self.0 == FALSE || self.0 == FALSE_SHORT {
-            Ok((Token::Bool(false), Resume::Here))
-        } else {
-            Err(())
-        }
-    }
-}
-
-impl State for BoolSub {
-    fn lex(&mut self, c: char) -> StateResult {
-        match c {
-            c if c.is_identifier_delimiter() => match self.handle_delimiter() {
-                Ok((token, resume)) => StateResult::Emit(token, resume),
-                Err(_) => {
-                    let msg = format!("Invalid character: {}", c);
-                    StateResult::Fail { msg }
-                }
-            },
-            _ => {
-                let buf = {
-                    let mut b = String::from(self.0.as_str());
-                    b.push(c);
-                    b
-                };
-                if TRUE.starts_with(&buf) || FALSE.starts_with(&buf) {
-                    StateResult::Advance { to: Box::new(BoolSub(buf)) }
-                } else {
-                    let msg = format!("Invalid character: {}", c);
-                    StateResult::Fail { msg }
-                }
-            }
-        }
-    }
-
-    fn none(&mut self) -> Result<Option<Token>, String> {
-        match self.handle_delimiter() {
-            Ok((token, _)) => Ok(Some(token)),
-            Err(_) => {
-                let msg = format!("Found EOF while trying to parse a bool");
-                Err(msg)
-            }
-        }
-    }
-}
-
-trait HashLexable {
-    fn is_tf(&self) -> bool;
-    fn is_slash(&self) -> bool;
-}
-
 impl HashLexable for char {
-    fn is_tf(&self) -> bool { "tfTF".contains(*self) }
+    fn is_bool_initial(&self) -> bool { "tf".contains(self.to_ascii_lowercase()) }
     fn is_slash(&self) -> bool { *self == '\\' }
 }

lexer/src/states/mod.rs

@@ -6,12 +6,11 @@ use std::fmt::Debug;
 use token::Token;
 
 mod begin;
+mod bool;
 mod hash;
-mod number;
 mod id;
 
 pub use self::begin::Begin;
-pub use self::number::BeginNumber;
 
 #[derive(Debug)]
 pub enum StateResult {
@@ -39,7 +38,15 @@ pub trait State: Debug {
 }
 
 impl StateResult {
+    pub fn advance(to: Box<State>) -> StateResult {
+        StateResult::Advance { to }
+    }
+
+    pub fn emit(token: Token, at: Resume) -> StateResult {
+        StateResult::Emit(token, at)
+    }
+
     pub fn fail(msg: &str) -> StateResult {
         StateResult::Fail { msg: msg.to_string() }
     }
-}
+}