Lexer now will straight away attempt to eat up any type or later
portions of an opcode rather than leaving everything but the root.
This means checking for type in the parser is a direct check against
the name rather than prefixed with a dot.
Checks are a bit more strong to cause more tokens to go straight to
symbol rather than getting checked after one routine in at on the
parser side.
Essentially a presult_t contains one of these:
1) A label construction, which stores the label symbol into
`label` (PRES_LABEL)
2) An instruction that calls upon a label, storing the instruction
in `instruction` and the label name in `label` (PRES_LABEL_ADDRESS)
3) An instruction that uses a relative address offset, storing the
instruction in `instruction` and the offset wanted into
`relative_address` (PRES_RELATIVE_ADDRESS)
4) An instruction that requires no further processing, storing the
instruction into `instruction` (PRES_COMPLETE_INSTRUCTION)
In the processing stage, we resolve all calls by iterating one by one
and maintaining an absolute instruction address. Pretty nice, lots
more machinery involved in parsing now.
Much simpler, uses a switch case which is a much faster method of
doing the parsing. Though roughly equivalent in terms of LOC, I feel
that this is more extensible
Introduced some functions to parse differing types of opcodes. Use
the same style of a.b.c... for namespacing or type specification for
certain opcodes. Bit hacky and not tested, but does work.
Parse errors can be reported with an exact location using the token
column, line.