Pass over whitespace and count lines

src/lexer/char.rs

@@ -10,6 +10,7 @@ pub trait Lexable {
     fn is_identifier_initial(&self) -> bool;
     fn is_identifier_subsequent(&self) -> bool;
     fn is_identifier_single(&self) -> bool;
+    fn is_newline(&self) -> bool;
 }
 
 impl Lexable for char {
@@ -32,5 +33,9 @@ impl Lexable for char {
     fn is_identifier_single(&self) -> bool {
         charset::identifier_singles().contains(&self)
     }
+
+    fn is_newline(&self) -> bool {
+        *self == '\n'
+    }
 }
 

src/lexer/mod.rs

@@ -22,6 +22,7 @@ pub struct Lexer {
     input: String,
     begin: usize,
     forward: usize,
+    line: u32,
     state: State,
 }
 
@@ -31,6 +32,7 @@ impl Lexer {
             input: input,
             begin: 0,
             forward: 0,
+            line: 1,
             state: State::Initial,
         }
     }
@@ -83,6 +85,12 @@ impl Lexer {
             self.state = State::Identifier;
             self.advance();
         }
+        else if c.is_whitespace() {
+            if c.is_newline() {
+                self.line += 1;
+            }
+            self.advance();
+        }
     }
 
     /// Handle self.state == State::Identifier