Make li_apply a bit more efficient.

Signed-off-by: Casey Dwyer <caseydwyer@gmail.com>
Add userdata type.

Signed-off-by: Casey Dwyer <caseydwyer@gmail.com>
Add stack trace.

Signed-off-by: Casey Dwyer <caseydwyer@gmail.com>
Add bytevector userdata..

Signed-off-by: Casey Dwyer <caseydwyer@gmail.com>
Add opt flag to compile experimental types like bytevector.

Signed-off-by: Casey Dwyer <caseydwyer@gmail.com>
Test case-sensitivity.

Signed-off-by: Casey Dwyer <caseydwyer@gmail.com>
Don't pop from the callstack be evaluating an expression.

Signed-off-by: Casey Dwyer <caseydwyer@gmail.com>