#[macro_use]
extern crate lazy_static;

pub mod assembler;
pub mod errors;
pub mod node;
pub mod object;
pub mod opcodes;
pub mod parser;

/// Mapping defines structures for laying out how the code will be assembled
/// both on memory and on the ROM file itself. Notice that we take a different
/// approach than 'cc65' because that compiler has to take into account a
/// myriad of machines that had the MOS 6502 processor. Here we have a clear
/// target and we can be more specific. That is, the community has settled on a
/// very specific ROM file format, and hence the "linker configuration" turns
/// out to be simpler. The code here takes it into consideration by defining
/// three regions on the ROM file:
///
///   1. The header (i.e. `SectionType::Header`) will be allocated exactly on
///      the first 16 bytes of the file. Moreover, the first 6 bytes are
///      absolutely mandatory to be filled by the programmer.
///   2. The PRG ROM (i.e. `SectionType::PrgRom`) will be allocated next to the
///      header (i.e. trainer support is not available on this assembler). This
///      section is laid out in blocks of 8KB and contains the program.
///   3. The CHR ROM (i.e. `SectionType::ChrRom`) will be allocated just after
///      the PRG ROM and is laid out in blocks of 4KB, containing the ROM data (if
///      available).
///
/// This is the layout for the ROM file itself, but it can itself be subdivided
/// into "mappings" (i.e. `Mapping`). A Mapping is a configuration inside of
/// one of these three sections. For a simple section like the header having
/// only one mapping will be enough, but for PRG ROM we might define a mapping
/// for each bank, for example. And even in simple scenarios, it's quite usual
/// to split this section at least with "CODE" (which contains the actual
/// program), and "VECTORS" (6 bytes containing the addresses for the vectors
/// for a 6502 processor). A Mapping contains quite a lot of info, but you can
/// think of it as a way to subdivide a section, defining stuff like where it
/// starts, its size, how to fill it if the programmer did not occupy the
/// region fully, etc.
///
/// Inside of a mapping there might be multiple segments. This is in turn a way
/// to further subdivide the memory region, and it defines contiguous space
/// inside of a mapping. This way, regardless of where you define a segment,
/// there are some guarantees on the order.
pub mod mapping;
