roachsinai

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!

roachsinai

/* recursive mkdir based on
http://nion.modprobe.de/blog/archives/357-Recursive-directory-creation.html
*/
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>

#define PATH_MAX_STRING_SIZE 256

roachsinai

#!/bin/bash

# This script is used to complete the output of the docker stats command.
# The docker stats command does not compute the total amount of resources (RAM or CPU)

# Get the total amount of RAM, assumes there are at least 1024*1024 KiB, therefore > 1 GiB
#HOST_MEM_TOTAL=$(grep MemTotal /proc/meminfo | awk '{print $2/1024/1024}')
DOCKER_MEM_TOTAL=$(docker info | grep Memory | awk '{print $3}' | grep -o '[0-9]*\.[0-9]*')

# Get the output of the docker stat command. Will be displayed at the end

roachsinai

# origin link: https://gist.github.com/roachsinai/faf8ac80860065a7e78adc0b25abb445

# compilation process: https://en.wikibooks.org/wiki/C%2B%2B_Programming/Programming_Languages/C%2B%2B/Code/Compiler/Linker
# Shared library concept: http://ehuss.com/shared/

# 1. Creating the shared library
# Command reference: https://www.oreilly.com/library/view/c-cookbook/0596007612/ch01s05.html
g++ -dynamiclib -fPIC shared.cpp -o shared.so # MacOS
g++ -fPIC -shared shared.cpp -o shared.so # Linux

roachsinai

void PrintA(void);
void PrintB(void);

int main(int argc, char *argv[])
{
  PrintA();
  PrintB();
  return 0;
}

roachsinai

[custom]
;解决DNS泄露，无分流群组
ruleset=🚀 节点选择,[]DOMAIN-SUFFIX,leetcode.cn
ruleset=🚀 节点选择,[]DOMAIN-SUFFIX,leetcode.com
ruleset=🚀 节点选择,[]DOMAIN-SUFFIX,xn--ngstr-lra8j.com
ruleset=🚀 节点选择,[]DOMAIN-SUFFIX,services.googleapis.cn
ruleset=🚀 节点选择,https://raw.githubusercontent.com/ACL4SSR/ACL4SSR/master/Clash/Ruleset/GoogleCNProxyIP.list
ruleset=DIRECT,https://raw.githubusercontent.com/ACL4SSR/ACL4SSR/master/Clash/LocalAreaNetwork.list
ruleset=DIRECT,https://raw.githubusercontent.com/ACL4SSR/ACL4SSR/master/Clash/UnBan.list
ruleset=DIRECT,https://raw.githubusercontent.com/ACL4SSR/ACL4SSR/master/Clash/ChinaDomain.list

roachsinai

// https://www.zhihu.com/question/33084689/answer/58994758

#include <stdio.h>
#include <string.h>

typedef struct inst
{
    unsigned char code; // 指令
    unsigned char cond; // 执行该指令的条件
    short p1, p2; // 参数1、2

roachsinai

#include <cstddef>
#include <cstdlib>

template <typename R, auto getter, auto setter, size_t (*offset)()>
struct property {
    inline R *self() {
        return reinterpret_cast<R *>(reinterpret_cast<size_t>(this) - offset());
    }
    inline operator auto() { return (self()->*getter)(); }
    inline void operator=(auto t) { (self()->*setter)(t); }

roachsinai

#!/usr/bin/env python
import sys
import subprocess
from pathlib import Path


result = subprocess.run(sys.argv[1:], capture_output=True)
result.stderr = result.stderr.lower()

roachsinai

Table Of Content

Skip to the relevant sections if needed.

• 2-min tutorial to do it the quick-and-dirty-way
• Concepts for resolving Git conflicts
• Setting up different editors / tool for using git mergetool
  • Finding out what mergetool editors are supported
• mergetool simple code example for vimdiff
  • Resolving conflict from a Git pull
• Other great references and tutorials