Matt Elliott elliottmatt

Falsehoods that Ethereum programmers believe

I recently stumbled upon Falsehoods programmers believe about time zones, which got a good laugh out of me. It reminded me of other great lists of falsehoods, such as about names or time, and made me look for an equivalent for Ethereum. Having found none, here is my humble contribution to this set.

About Gas

Calling `estimateGas` will return the gas required by my transaction

Calling estimateGas will return the gas that your transaction would require if it were mined now. The current state of the chain may be very different to the state in which your tx will get mined. So when your tx i

gif-from-tweet

There are so many great GIFs out there and I want to have copies of them. Twitter makes that harder than it should be by converting them to MP4 and not providing access to the source material. To make it easier, I made a bash pipeline that takes a tweet URL and a filename, extracts the MP4 from that tweet and uses ffmpeg to convert back to GIF.

Dependencies

ffmpeg
- macOS: brew install ffmpeg
- Ubuntu/Debian: apt install ffmpeg

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

UPDATE: A better way! (August 2015)

As pointed out by @johntyree in the comments, using git reflog is easier and more reliable. Thanks for the suggestion!

 $ git reflog
1ed7510 HEAD@{1}: checkout: moving from develop to 1ed7510
3970d09 HEAD@{2}: checkout: moving from b-fix-build to develop
1ed7510 HEAD@{3}: commit: got everything working the way I want
70b3696 HEAD@{4}: commit: upgrade rails, do some refactoring

Setup

git clone <repo>

clone the repository specified by ; this is similar to "checkout" in some other version control systems such as Subversion and CVS

Add colors to your ~/.gitconfig file:

	www,719407
	api,69552
	eks,67581
	svc,67131
	cloudapp,65945
	vpn,55659
	bastion,53840
	ax,40676
	dev,38756
	operations,35663

	/**
	* @dev OpcodeChecker processes contract code to generate a bitmap of used opcodes.
	*
	* DO NOT USE: See the vulnerability identified by Recmo below. A patch will be provided soon.
	*
	* The generated bitmap can be used to enforce whitelisting and blacklisting on contract code.
	* Bit n of the bitmap is set iff opcode n is used. For instance, the presence of the STOP opcode
	* will result in bit 0 of the bitmap being set.
	*
	* A best-effort attempt is made to skip over unreachable data, but there may be false positives.

	aa.je
	ae.je
	ae.gg
	ae.ht
	af.je
	af.cx
	af.gg
	af.gl
	af.ht
	ah.je

	1033edge.com
	11mail.com
	123.com
	123box.net
	123india.com
	123mail.cl
	123qwe.co.uk
	126.com
	150ml.com
	15meg4free.com