Greg Hewgill
http://hewgill.com
Psil is a Lisp family language designed for close integration with Python.
Psil requires Python 3.1 or later.
To run a REPL (interactive read-eval-print-loop):
$ python3.1 psil.py
PSIL interactive mode
Use (quit) to exit
>
To run a Psil script in a file:
$ python3.1 psil.py hello.psil
hello world
or (on Unix-like systems):
$ ./hello.psil
hello world
To run Psil code from within Python:
#!/usr/bin/env python3.1
from psil.interpreter import psil
square = psil("""
(lambda (x)
(* x x))
""")
print(square(5))
A slightly more advanced example where the glob=globals() is needed so that
the Psil code can see back into the Python module for the fact function:
#!/usr/bin/env python3.1
from psil.interpreter import psil
fact = psil("""
(lambda (x)
(if (== x 0)
1
(* x (fact (- x 1)))))
""", glob=globals())
print(fact(5))
The psil.test file is a doctest module with many examples including macros.
To run the tests:
$ python3.1 psil.py --test