文宇祥 hackwaly

This is the predecessor of Mazeppa.

Supercompilation is a deep program transformation technique due to V. F. Turchin, a prominent computer scientist, cybernetician, physicist, and Soviet dissident. He described the concept as follows [^supercompiler-concept]:

A supercompiler is a program transformer of a certain type. The usual way of thinking about program transformation is in terms of some set of rules which preserve the functional meaning of the program, and a step-by-step application of these rules to the initial program. ... The concept of a supercompiler is a product of cybernetic thinking. A program is seen as a machine. To make sense of it, one must observe its operation. So a supercompiler does not transform the program by steps; it controls and observes (SUPERvises) the running of the machine that is represented by th

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	(* 这是我（预期，亦或是已经）在 ∞-type càfe summer school 上做的 talk，

	"从零教你手把手实现一个 MLTT 类型检查器"

	的内容稿。本 talk 计划以现场边讲解边手写代码的方式实现，
	所以虽然这份内容稿会尽量尝试还原 talk 的思路和逻辑，
	它的内容可能会与实际的 talk 有出入，建议有条件的人直接去听 talk 本身 *)

	(* 本次 talk 将会使用 OCaml 来实现一个 MLTT 类型检查器。
	你可能不会写 OCaml，但这没有关系。本次 talk 只会使用以下的功能：

	(menhir
	(modules parser))

	(ocamllex lexer)

	(executable
	(name ex))

	#!/usr/bin/env python3
	import re, string
	START_SYMBOL = '<start>'
	RE_NONTERMINAL = re.compile('(<[^<> ]*>)')
	EPSILON = ''

	def fixpoint(f):
	def helper(arg):
	while True:
	sarg = str(arg)

	// Copied from typescript playground - https://www.typescriptlang.org/play/

	class Vector {

	constructor(public x: number, public y: number, public z: number) { }

	static times(k: number, v: Vector) {
	return new Vector(k * v.x, k * v.y, k * v.z);
	}

	import zipfile
	import xxtea
	import re
	import os

	# setXXTEAKeyAndSign

	apk = zipfile.ZipFile("xxxx.apk", "r")

	probe_file = []

	import struct

	_DELTA = 0x9E3779B9

	def _long2str(v, w):
	n = (len(v) - 1) << 2
	if w:
	m = v[-1]
	if (m < n - 3) or (m > n): return ''
	n = m


	(* Good morning everyone, I'm currently learning ocaml for one of my CS class and needed to implement
	an avl tree using ocaml. I thought that it would be interesting to go a step further and try
	to verify the balance property of the avl tree using the type system. Here's the resulting code
	annotated for people new to the ideas of type level programming :)
	*)

	(* the property we are going to try to verify is that at each node of our tree, the height difference between
	the left and the right sub-trees is at most of 1. *)



	(** [dir_is_empty dir] is true, if [dir] contains no files except
	* "." and ".."
	*)
	let dir_is_empty dir =
	Array.length (Sys.readdir dir) = 0

	(** [dir_contents] returns the paths of all regular files that are
	* contained in [dir]. Each file is a path starting with [dir].