Braces (the tiny scheme compiler and VM)

Brace for impact

State

This is beyond the state where it's just dabbling around. However at this point I don't have any intentions to turn it into something for real world usage (I'm not sure I could even if I tried). It will likely remain a play ground where I just try out ideas. I'll just see where it takes me.

Usage

Start the REPL and play around with it

make repl 

Language Support

• literals
  • bool
  • symbol
  • char
  • number
  • vector
  • byte-vector
  • proper list
  • improper list
  • string
  • quoted constants
• variables
• conditionals
• lambda expressions
• procedure calls
• assignments
• quasi-quoted expression

Compiler

• sexp parser
• expression parser
• basic code generator
• collect all errors in sexp parser
• collect all errors in expr parser
• bytecode serialization
• libraries
• optimization pass
• identify tail calls
• quasi quote

Macros

• add macro expansion phase
• add syntactic closure macro system

Errors

• fix backtraces
• improve error reporting for sexp parser
• improve error reporting for expressions

VM

• optimise tail calls
• closures
• continuations
• optimize stack

Debugger

• generate DWARF debug information

GC

Well there is none :D I probably should build one or maybe not.

Repl

• command support
• bracket matching
• completion of bound identifiers

Continuations

• figure out how to implement them

Problems

There are plenty :D

• Runtime representation of values isn't at all optimised. It likely uses way too many allocations and holds the types wrong
• The parser bails after the first error (you'd want to collect all)
• I'm not sure if the custom ParseResult I use is really needed? (I will have to figure that out)
• No proper macro expander yet. (There is an expansion phase which expands using rust code but that's very limited for now)
• No support for internal defines (we might get away by adding an expansion to letrec*)
• I'm not sure the location tracking works all the time