Implement return (doesn't work yet from a nested block).
Pass test 17.

Add conversions from number and string to integer.
Implement nqp::log, pass test 83.
Implement nqp::radix.
Add passing test 48 to run_tests.
Passing named arguments.
Pass test 23.

Implement named arguments.
Pass test 42.

nqp.to_num(string) works.
Add passing test 83 to run_tests.: