char literals

src/codegen_x86_64.rs

@@ -511,6 +511,13 @@ Array.free:
                 TokenType::Number => {
                     emit!(&mut self.output, "    mov rax, {}", token.lexeme);
                 }
+                TokenType::Char => {
+                    emit!(
+                        &mut self.output,
+                        "    mov rax, {}",
+                        token.lexeme.chars().nth(1).unwrap() as u8
+                    );
+                }
                 TokenType::String => {
                     // TODO: actual string parsing in the tokenizer
                     let value = &token.lexeme[1..token.lexeme.len() - 1]

src/parser.rs

@@ -427,6 +427,7 @@ impl Parser {
     fn primary(&mut self) -> Result<Expr, ZernError> {
         if self.match_token(&[
             TokenType::Number,
+            TokenType::Char,
             TokenType::String,
             TokenType::True,
             TokenType::False,

src/std.zr

@@ -12,7 +12,7 @@ func print_i64[x: I64] : I64
     return 0
 
 func String.is_whitespace[c: U8] : Bool
-    return c == 10 || c == 32 || c == 13 || c == 9
+    return c == ' ' || c == 10 || c == 13 || c == 9
 
 func String.concat[a: String, b: String] : String
     let c: String = malloc(strlen(a) + strlen(b) + 1)
@@ -83,7 +83,7 @@ func IO.write_file[path: String, content: String] : I64
     return 0
 
 func U8.parse_i64[c: U8]: I64
-    return c - 48
+    return c - '0'
 
 func I64.to_string[n: I64] : String
     let x: String = malloc(21)
@@ -183,17 +183,17 @@ func Crypto.hex_encode[s: String] : String
     return out
 
 func Crypto.from_hex_digit[d: U8] : I64
-    if d == 97
+    if d == 'a'
         return 10
-    if d == 98
+    if d == 'b'
         return 11
-    if d == 99
+    if d == 'c'
         return 12
-    if d == 100
+    if d == 'd'
         return 13
-    if d == 101
+    if d == 'e'
         return 14
-    if d == 102
+    if d == 'f'
         return 15
     return U8.parse_i64(d)
 
@@ -268,12 +268,11 @@ func Crypto.base64_encode[s: String] : String
         j = j + 4
 
     let padding: I64 = s_len % 3
-    let equals: U8 = String.nth("=", 0)
     if padding == 1
-        String.set(output, j-2, equals)
-        String.set(output, j-1, equals)
+        String.set(output, j-2, '=')
+        String.set(output, j-1, '=')
     else if padding == 2
-        String.set(output, j-1, equals)
+        String.set(output, j-1, '=')
 
     String.set(output, j, 0)
     return output
@@ -285,7 +284,7 @@ func Crypto.base64_decode[s: String] : String
     let i: I64 = 0
     let j: I64 = 0
 
-    while String.nth(s, s_len-1) == 61
+    while String.nth(s, s_len-1) == '='
         s_len = s_len - 1
 
     while i < s_len

src/tokenizer.rs

@@ -30,6 +30,7 @@ pub enum TokenType {
 
     Identifier,
     String,
+    Char,
     Number,
     True,
     False,
@@ -208,6 +209,14 @@ impl Tokenizer {
                     self.add_token(TokenType::Less)
                 }
             }
+            // TODO: escape sequences
+            '\'' => {
+                self.advance();
+                if !self.match_char('\'') {
+                    return error!(self.loc, "expected ' after char literal");
+                }
+                self.add_token(TokenType::Char);
+            }
             '"' => {
                 while !self.eof() && self.peek() != '"' {
                     if self.peek() == '\n' {