- rc file
- plugins
- auto-return
- replace /^=/ with 'return'
- handle locals
- override debug.debug
- save old results
- pretty print results
- tab completion
- handle locals (debug.sethook?)
- some sort of debugger?
- override debug.debug?
- save old results (ala Python's _)
- pretty print results (like Data::Dumper)
- don't contaminate globals
- editline
- tab completion (__complete metamethod)
- "safe" evaluation (don't allow calling of C functions, except for those in a whitelist?)
- web-based REPL implementation
- irc-based REPL implementation
- safety hooks
- displaystack instead of displayerror(err)? (should xpcall return false, stack_table?)
- visual REPL (like Factor; being able to print multi-colored/multi-sized text, images, etc)
- syntax highlighting
- paren/brace matching?
- snippets?
- code navigation (go to definition?)
- history
- repls that "attach" to different objects (ie. inspect a single object; self is that object. completions happen against that object?)
- browsable/searchable REPL history
- safe termination of evaluated code (if I Control-C during an evaluation)
- store stdout/stderr output in a variable somewhere?