feat: finish error handling for lexing

CHANGELOG.md

@@ -35,7 +35,5 @@ Now in Zig!
 - [x] Parse minimal variable binding
 - [x] Parse minimal statement
 - [x] Parse minimal module
-- [x] Generate error messages on number lexing
-- [x] Generate error messages on string lexing
-
+- [x] Recuperate errors & generate error messages for the lexer
 

src/01_lexic/comment.zig

@@ -2,13 +2,19 @@ const std = @import("std");
 const assert = std.debug.assert;
 const token = @import("./token.zig");
 const utils = @import("./utils.zig");
+const errors = @import("errors");
 
 const Token = token.Token;
 const TokenType = token.TokenType;
 const LexError = token.LexError;
 const LexReturn = token.LexReturn;
 
-pub fn lex(input: []const u8, start: usize) LexError!?LexReturn {
+pub fn lex(
+    input: []const u8,
+    start: usize,
+    err: *errors.ErrorData,
+    alloc: std.mem.Allocator,
+) LexError!?LexReturn {
     const cap = input.len;
     assert(start < cap);
 
@@ -24,6 +30,10 @@ pub fn lex(input: []const u8, start: usize) LexError!?LexReturn {
         while (current_pos < cap and input[current_pos] != '\n') {
             // check for CR, and throw error
             if (input[current_pos] == '\r') {
+                try err.init("Usage of CRLF", current_pos, current_pos + 1, alloc);
+                try err.add_label("There is a line feed (CR) here", current_pos, current_pos + 1);
+                err.set_help("All THP code must use LF newline delimiters.");
+
                 return LexError.CRLF;
             }
             current_pos += 1;
@@ -37,7 +47,7 @@ pub fn lex(input: []const u8, start: usize) LexError!?LexReturn {
 
 test "should lex comment until EOF" {
     const input = "// aea";
-    const output = try lex(input, 0);
+    const output = try lex(input, 0, undefined, std.testing.allocator);
 
     if (output) |tuple| {
         const t = tuple[0];
@@ -50,7 +60,7 @@ test "should lex comment until EOF" {
 
 test "should lex comment until newline (LF)" {
     const input = "// my comment\n// other comment";
-    const output = try lex(input, 0);
+    const output = try lex(input, 0, undefined, std.testing.allocator);
 
     if (output) |tuple| {
         const t = tuple[0];
@@ -63,13 +73,15 @@ test "should lex comment until newline (LF)" {
 
 test "shouldn lex incomplete comment" {
     const input = "/aa";
-    const output = try lex(input, 0);
+    const output = try lex(input, 0, undefined, std.testing.allocator);
     try std.testing.expect(output == null);
 }
 
 test "should fail on CRLF" {
     const input = "// my comment\x0D\x0A// other comment";
-    _ = lex(input, 0) catch |err| {
+    var errdata: errors.ErrorData = undefined;
+    _ = lex(input, 0, &errdata, std.testing.allocator) catch |err| {
+        defer errdata.deinit();
         try std.testing.expectEqual(LexError.CRLF, err);
         return;
     };

src/01_lexic/root.zig

@@ -101,17 +101,29 @@ pub fn tokenize(
             current_pos = tuple[1];
 
             try tokens.append(t);
+            continue;
         }
+
         // attempt to lex a comment
-        else if (try comment.lex(input, actual_next_pos)) |tuple| {
+        const comment_lex = comment.lex(input, actual_next_pos, &current_error, alloc) catch |e| switch (e) {
+            LexError.CRLF => {
+                try err_arrl.append(current_error);
+                current_pos = ignore_until_whitespace(input, actual_next_pos);
+                continue;
+            },
+            else => return e,
+        };
+        if (comment_lex) |tuple| {
             assert(tuple[1] > current_pos);
             const t = tuple[0];
             current_pos = tuple[1];
 
             try tokens.append(t);
+            continue;
         }
+
         // attempt to lex an operator
-        else if (try operator.lex(input, actual_next_pos)) |tuple| {
+        if (try operator.lex(input, actual_next_pos)) |tuple| {
             assert(tuple[1] > current_pos);
             const t = tuple[0];
             current_pos = tuple[1];