From 148ede7f0f42f0ccb1620b13d91f35d0c7d04c2f Mon Sep 17 00:00:00 2001
From: Titus Wormer <tituswormer@gmail.com>
Date: Fri, 29 Jul 2022 10:49:07 +0200
Subject: Refactor to work on bytes (`u8`)

---
 src/util/slice.rs | 44 ++++++++++++++++++--------------------------
 1 file changed, 18 insertions(+), 26 deletions(-)

(limited to 'src/util/slice.rs')

diff --git a/src/util/slice.rs b/src/util/slice.rs
index 14fd527..cd3641e 100644
--- a/src/util/slice.rs
+++ b/src/util/slice.rs
@@ -48,17 +48,21 @@ impl<'a> Position<'a> {
 /// Includes information on virtual spaces before and after the chars.
 #[derive(Debug)]
 pub struct Slice<'a> {
-    pub chars: &'a [char],
+    pub bytes: &'a [u8],
     pub before: usize,
     pub after: usize,
 }
 
 impl<'a> Slice<'a> {
     /// Get the slice belonging to a position.
-    pub fn from_point(list: &'a [char], point: &Point) -> Slice<'a> {
+    pub fn from_point(bytes: &'a [u8], point: &Point) -> Slice<'a> {
         let mut before = point.vs;
         let mut start = point.index;
-        let end = if start < list.len() { start + 1 } else { start };
+        let end = if start < bytes.len() {
+            start + 1
+        } else {
+            start
+        };
 
         // If we have virtual spaces before, it means we are past the actual
         // character at that index, and those virtual spaces.
@@ -68,14 +72,14 @@ impl<'a> Slice<'a> {
         };
 
         Slice {
-            chars: if start < end { &list[start..end] } else { &[] },
+            bytes: if start < end { &bytes[start..end] } else { &[] },
             before,
             after: 0,
         }
     }
 
     /// Get the slice belonging to a position.
-    pub fn from_position(list: &'a [char], position: &Position) -> Slice<'a> {
+    pub fn from_position(bytes: &'a [u8], position: &Position) -> Slice<'a> {
         let mut before = position.start.vs;
         let mut after = position.end.vs;
         let mut start = position.start.index;
@@ -96,15 +100,16 @@ impl<'a> Slice<'a> {
         }
 
         Slice {
-            chars: &list[start..end],
+            bytes: &bytes[start..end],
             before,
             after,
         }
     }
 
     /// To do.
+    // To do: rename to `len`?
     pub fn size(&self) -> usize {
-        self.chars.len() + self.before + self.after
+        self.bytes.len() + self.before + self.after
     }
 
     // To do:
@@ -112,27 +117,13 @@ impl<'a> Slice<'a> {
     // to implement an `as_str`.
 
     /// To do.
-    pub fn head(&self) -> Option<char> {
+    pub fn head(&self) -> Option<u8> {
         if self.before > 0 {
-            Some(' ')
-        } else if self.chars.is_empty() {
+            Some(b' ')
+        } else if self.bytes.is_empty() {
             None
         } else {
-            Some(self.chars[0])
-        }
-    }
-
-    /// To do.
-    pub fn tail(&self) -> Option<char> {
-        if self.after > 0 {
-            Some(' ')
-        } else {
-            let index = self.chars.len();
-            if index > 0 {
-                Some(self.chars[index - 1])
-            } else {
-                None
-            }
+            Some(self.bytes[0])
         }
     }
 
@@ -144,7 +135,8 @@ impl<'a> Slice<'a> {
             string.push(' ');
             index -= 1;
         }
-        string.push_str(&self.chars.iter().collect::<String>());
+        // To do: invalid UTF8?
+        string.push_str(std::str::from_utf8(self.bytes).unwrap());
         index = self.after;
         while index > 0 {
             string.push(' ');
-- 
cgit