gistfile1.txt

use "../core"

enum Token
	None
	Unknown
	Id

struct Lexer
	struct State
		lexer *Lexer
		type Token
		start *char
		stop *char

		end()
			stop = lexer.i.pos

		str()
			return String.from_data(start, int_ptr stop - int_ptr start)

	struct Input
		pos *char
		end *char

		step()
			pos = ptr_idx(pos, 1)
			return *pos

		c()
			return *pos

		eq(c char)
			return *pos == c

	tok State
	content String 
	i Input
	jump_table Table(256, () -> ())

	set(str)
		content = str
		IO.puts("content: " ~ content)
		i.pos = content.data
		i.end = ptr_idx(content.data, content.size)
		tok.lexer = self
		step()

	action create
		setup_table()

	setup_table()
		.set_chars = |start char, stop, f|
			for_range(start, stop, |i|
				jump_table(force_cast i) = f)

		set_chars(0, 255, unknown)

	step()
		IO.puts("step " ~ show(force_cast[uint] i.c()))
		tok.type = Token.None
		tok.start = i.pos

		jump_table(force_cast i.c())()

		assert -> int_ptr tok.stop >= int_ptr tok.start
		assert -> tok.type != Token.None

	unknown()
		IO.puts("Unknown")
		i.step()
		tok.type = Token.None
		tok.end()

		IO.puts("Unknown character: " ~ tok.str())

		step()