CORE LANGUAGE FEATURES

- Traces
- Closures, exported as a command that can set/get/unset elements
  from a dictionary associated with the current procedure.
  The [closure] command should allow to perform this operations,
  and to access the closure of a procedure from another one.

CORE COMMANDS

- All the missing standard core commands not related to I/O, namespaces, ...
- [tail] command for programmer-driven tail recursion optimization
- The current [expr] needs a lot of work, expecially operators && and ||
  are not lazy. Math functions are not present but probably will never
  be added as expr functions, but as Tcl commands, like [sin], [cos] and
  so on.

COMMANDS NOT IN TCL BUT THAT SHOULD BE IN JIM

- commands to operate on sets (that are lists semantically).

EXTENSIONS

- Regexp extension
- OOP system (this will possibly part of the core)

SPEED OPTIMIZATIONS

- Cache call frames instead to free/realloc they at every proc call.

IMPLEMENTATION ISSUES

- Objects lazy free.
- [split $string {}] should generate a list with Jim_Obj of chars shared.
- [closure] command to set/get procedures-specific closure variables.
  For example:
- Remove SetTypeFromAny() method from the Jim_ObjType structure.
  It's not useful, and it may be useful to have different prototypes
  for the Set*FromAny() procedures of different types.