Added linelocation to all errors

src/parser/linelocation.rs

@@ -0,0 +1,59 @@
+use std::cmp;
+use std::ops::Add;
+use std::ops::AddAssign;
+use std::cmp::Ordering;
+
+/// Specifies the location of a token in an input string.
+#[derive(Debug)]
+#[derive(Copy, Clone)]
+pub struct LineLocation {
+	pub pos: usize,
+	pub len: usize
+}
+
+impl LineLocation {
+	pub fn zero(&self) -> bool {
+		return self.pos == 0 && self.len == 0
+	}
+}
+
+impl PartialEq for LineLocation {
+	fn eq(&self, other: &Self) -> bool {
+		self.pos == other.pos &&
+		self.len ==other.len
+	}
+}
+
+impl PartialOrd for LineLocation {
+	fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+		return self.pos.partial_cmp(&other.pos);
+	}
+}
+
+impl Add for LineLocation {
+	type Output = Self;
+
+	fn add(self, other: Self) -> Self::Output {
+		if self.zero() { return other; }
+		if other.zero() { return self; }
+
+		let start = cmp::min(self.pos, other.pos);
+		let end = cmp::max(self.pos+self.len-1, other.pos+other.len-1);
+		return LineLocation{
+			pos: start,
+			len: end - start+1
+		};
+	}
+}
+
+impl AddAssign for LineLocation where {
+	fn add_assign(&mut self, other: Self) {
+		if self.zero() {*self = other}
+		if other.zero() { return }
+
+		let start = cmp::min(self.pos, other.pos);
+		let end = cmp::max(self.pos+self.len-1, other.pos+other.len-1);
+		self.pos = start;
+		self.len = end - start + 1;
+	}
+}