ofan

Lisp interpreter in 90 lines of C++

I've enjoyed reading Peter Norvig's recent articles on Lisp. He implements a Scheme interpreter in 90 lines of Python in the first, and develops it further in the second.

Just for fun I wondered if I could write one in C++. My goals would be

1. A Lisp interpreter that would complete Peter's Lis.py test cases correctly...
2. ...in no more than 90 lines of C++.

Although I've been thinking about this for a few weeks, as I write this I have not written a line of the code. I'm pretty sure I will achieve 1, and 2 will be... a piece of cake!

ofan

#!/bin/bash
if [ -z "`ps aux | grep 'emacs --daemon'|grep -v grep`" ];then
    echo "Daemon is not started,starting daemon..."
    emacs --daemon >/dev/null 2>&1
fi

list=`wmctrl -l|grep "emacs"`
if [ -z "$list" ];then
    emacsclient -nc $*
else

ofan

import sys
def fac(n):
    if n==0:
        return 1
    r=1
    for i in xrange(2,n+1):
        r*=i
    return r

if __name__ == '__main__':

ofan

import sys
from gmpy import *
def fac(n):
    if n==0:
        return 1
    r=mpz(1)
    for i in xrange(2,n+1):
        r*=i
    return r

ofan

import sys
from gmpy import *

if __name__ == '__main__':
    print fac(int(sys.argv[1]))

ofan

traceroute to 61.184.202.221 (61.184.202.221), 30 hops max, 40 byte packets
 1  192.168.0.1 (192.168.0.1)  0.587 ms  0.516 ms  0.525 ms
 2  * 61.184.202.221 (61.184.202.221)  288.025 ms *

ofan

PING 61.184.202.221 (61.184.202.221) 56(84) bytes of data.
64 bytes from 61.184.202.221: icmp_req=1 ttl=116 time=279 ms
64 bytes from 61.184.202.221: icmp_req=2 ttl=116 time=278 ms
64 bytes from 61.184.202.221: icmp_req=3 ttl=116 time=278 ms
64 bytes from 61.184.202.221: icmp_req=4 ttl=116 time=280 ms

ofan

# coding:utf-8

if __name__=='__main__':
    for i in range(4):
        raw_input()

    count=1
    first=''
    second=''
    while True:

ofan

ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAraUohxjNFuSC8sBJm6MlYbRDsb5H+ID20E6N6Ky1tss7oZqn/RyothoOwCAa44UmwBvV7dpD4pJ0xNtNzZAIs8hAYAH/pzmzwZOjjZqLQ+YQ6vSyoumbxq05yLr07gy7v61K4Wi8nUWlufdOpaV1QeHtEzZqsBKEVlK+hlRCTzO/8iCc7iQzIXM46jeaRwOuV7f5NdfiRLX8Xp6EfA8rRP8Qx+UPMESYVY4qLtLVhIv15sf8Lu6M0nXWW5GOmw2f1ToiNJG7krueREFNHvWXs9/yjinbzbC+ZIlyXbt/Eabyj0w/WCt7ZwT/HkDosPYMCMcPIdEF2xTdqti+PzPDxQ== odayfans@gmail.com

ofan

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