Peter Law PeterJCLaw

Note: I've recently discoverded the git filter-repo tool, which is almost certainly better than the instructions below.

Steps for extracting files from one git repo into another:

Grab a copy of the utils files from this gist (and ensure they're marked as executable)
Clone the original repo to a new location: git clone $ORIGINAL /tmp/new-repo && cd /tmp/new-repo
Break the connection from the original repo: git remote remove origin
Create a branch of the starting point for easy reference

Originally noted 2018-11-14. I've since discovered unsquashfs (via https://unix.stackexchange.com/questions/80305/mounting-a-squashfs-filesystem-in-read-write) which is likely a simpler way to un-squash.

Un-squash:

mkdir squishy
sudo mount base/overlay.sr2017.2.squash squishy/ -t squashfs -o loop
mkdir /tmp/squoosh
find squishy/ -xdev -print0 | sudo cpio -pa0V /tmp/squoosh

How to make asynchronous coroutines be concurrent

It took me a couple of attempts to really get async in Python, partly I suspect because I'd encountered it in other languages (notably C#) and already had a mental model of how it should behave.

My initial approach was reading the PEPs and having a go at trying to create some asynchronous functions myself, rather than starting out using a library. My aim was to understand the internals, rather than learn a library, as I prefer to understand the nuts & bolts of things than just learn a particular API over the

	from typing import Any, Iterable, List, Tuple, Type, TypeVar, Union, Dict, Mapping, Generic

	K = TypeVar('K')
	T = TypeVar('T')
	T_co = TypeVar('T_co', covariant=True)
	V = TypeVar('V')

	list_of_string_type = [int] # type: List[Type[int]]

	from typing import Any, Iterable, List, Tuple, TypeVar

	T = TypeVar('T')
	TList = TypeVar('TList', bound=List[Any])

	untyped_list_str = ['abc', 'def']
	typed_list_str = ['abc', 'def'] # type: List[str]

	untyped_tuple_str = ('abc',)
	typed_tuple_str = ('abc',) # type: Tuple[str]

	from typing import Any, Callable, TypeVar

	R = TypeVar('R')
	T = TypeVar('T')
	TCallable = TypeVar('TCallable', bound=Callable[..., Any])


	def demo(num: int) -> str:
	return str(num)

	import functools
	from typing import Any, cast, TypeVar, Callable

	R = TypeVar("R")

	# Roughly as suggested in https://github.com/davidhalter/jedi/issues/1425#issuecomment-565711589,
	# though note that mypy complained about the arguments being `[...]` so I've
	# changed to just `...`
	def annotated_decorator(fn: Callable[..., R]) -> Callable[..., R]:
	return fn

	==> box: Adding box 'fedora/29-cloud-base' (v29.20181024.1) for provider: virtualbox
	box: Downloading: https://vagrantcloud.com/fedora/boxes/29-cloud-base/versions/29.20181024.1/providers/virtualbox.box
	box: Download redirected to host: download.fedoraproject.org
	box: Download redirected to host: www.mirrorservice.org
	/opt/vagrant/embedded/lib/ruby/2.4.0/fileutils.rb:1299:in `utime': Operation not permitted @ utime_internal - /home/peter/.vagrant.d/boxes/fedora-VAGRANTSLASH-29-cloud-base/29.20181024.1/virtualbox/metadata.json (Errno::EPERM)
	from /opt/vagrant/embedded/lib/ruby/2.4.0/fileutils.rb:1299:in `copy_metadata'
	from /opt/vagrant/embedded/lib/ruby/2.4.0/fileutils.rb:419:in `block in copy_entry'
	from /opt/vagrant/embedded/lib/ruby/2.4.0/fileutils.rb:1394:in `wrap_traverse'
	from /opt/vagrant/embedded/lib/ruby/2.4.0/fileutils.rb:413:in `copy_entry'
	from /opt/vagrant/embedded/lib/ruby/2.4.0/fileutils.rb:471:in `rescue in block in mv'

	Team Min-gap Count Gaps
	25 4 1 [32, 8, 11, 10, 6, 8, 9, 10, 10, 7, 10, 4, 13]
	23 4 2 [31, 11, 10, 9, 8, 4, 8, 14, 4, 15, 5, 9, 10]
	29 4 1 [33, 7, 12, 7, 11, 9, 7, 4, 12, 5, 11, 9, 7]
	1 4 1 [26, 10, 9, 9, 11, 11, 9, 11, 10, 6, 4, 12, 9]
	3 4 1 [26, 12, 9, 9, 11, 11, 10, 4, 7, 8, 12, 7, 9]
	2 4 1 [26, 11, 9, 9, 11, 11, 10, 10, 9, 4, 7, 8, 9]
	7 4 1 [27, 11, 10, 9, 9, 10, 8, 11, 7, 13, 7, 4, 16]
	6 4 1 [27, 10, 8, 8, 10, 12, 8, 9, 14, 6, 12, 9, 4]
	9 4 1 [28, 8, 11, 6, 11, 13, 10, 10, 8, 4, 9, 11, 7]

	#!/usr/bin/env python3

	import argparse
	import functools
	import subprocess
	from pathlib import Path
	from typing import Sequence


	def compress(numbers: Sequence[int]) -> str: