add full grammar parsing

1 files changed, 11 insertions, 15 deletions

diff --git a/src/character.zig b/src/character.zig
index bd11ccd..10dd254 100644
--- a/src/character.zig
+++ b/src/character.zig
@@ -3,22 +3,12 @@ const std = @import("std");
 pub const Character = union(enum) {
 	const Self = @This();
 
-	pub const EPSILON: u8 = '_';
-	pub const END: u8 = 0;
+	pub const EPSILON: u9 = std.math.maxInt(u8) + 1;
+	pub const END: u9 = std.math.maxInt(u8) + 2;
 
 	epsilon: void,
 	terminal: u8,
-	non_terminal: u8,
-
-	pub fn from_u8(c: u8) Self {
-		if (c == '_') {
-			return Self { .epsilon = void{} };
-		} else if (std.ascii.isUpper(c)) {
-			return Self { .non_terminal = c };
-		} else {
-			return Self { .terminal = c };
-		}
-	}
+	non_terminal: usize,
 
 	pub fn format(
 		self: *const Self,
@@ -31,8 +21,14 @@ pub const Character = union(enum) {
 
 		switch (self.*) {
 			.epsilon => _ = try writer.writeAll("ε"),
-			.terminal => |c| try writer.writeByte(c),
-			.non_terminal => |c| try writer.writeByte(c),
+			.terminal => |c| {
+				if (c == END) {
+					try writer.writeAll("$");
+				} else {
+					try writer.print("'{c}'", .{c});
+				}
+			},
+			.non_terminal => |index| try writer.print("<{}>", .{index}),
 		}
 	}
 };