Gonzalo gdebenito

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Focusing

Love Rubik's cubes. Learning backend technologies

gdebenito / abiArrayEncoding.sol

Last active February 12, 2019 22:23

	pragma solidity >=0.4.22 <0.6.0;
	contract AssemblyArray {
	function bar(uint[] calldata x, uint256 y) external pure
	returns (uint256 offset, uint256 length, uint256 x0, uint256 x1, uint256 y0) {
	assembly {
	calldatacopy(0x0,4,36)
	// x offset
	calldatacopy(0x20,68,100) // x length
	calldatacopy(0x40,100,132) // x[0]
	calldatacopy(0x60,132,164) // x[1]

gdebenito / callerAddressAssembly.sol

Created February 12, 2019 23:23

	pragma solidity >=0.4.22 <0.6.0;

	contract AssemblyAddr {
	function foo() public returns (uint256){
	assembly{
	mstore(0x0,caller)
	return(0x0,32)
	}
	}
	}

gdebenito / StorageOptimisation1.sol

Last active February 26, 2019 14:35

Here is an example how data is tightly packed with solidity compiler.

	pragma solidity >=0.4.22 <0.6.0;

	contract StorageOptimization {

	uint16 a;
	uint16 b;
	uint16 c;
	uint16 d;
	uint64 e;
	uint128 f;

gdebenito / dynamicArray.sol

Created February 28, 2019 22:41

How does solidity stores dynamic arrays in a ethereum smart contract?

	pragma solidity >=0.4.22 <0.6.0;

	contract DynamicArray {

	uint256[] store;

	function getAssembly(uint256 _idx) external view returns(uint256 _value) {
	bytes32 dir = keccak256(abi.encodePacked(uint256(0))); // stored at slot 0
	assembly{
	_value := sload(add(dir,_idx)) // access to keccak256 of slot 0 plus offset

gdebenito / mappingStorage.sol

Created February 28, 2019 23:18

How does Solidity stores mapping in a ehtereum smart contract?

	pragma solidity >=0.4.22 <0.6.0;

	contract Mapping {

	mapping(string => uint256) store; // stored at slot 0

	function getAssembly(string calldata _key) external view returns(uint256 _value) {
	bytes32 dir = keccak256(abi.encodePacked(_key,uint256(0))); // concatenation of key and slot
	assembly{
	_value := sload(dir) // load value

gdebenito / insertDate.sh

Last active June 9, 2019 07:37

This script insert date in all files of a directory. This script is a test between sequentially and forking the process

	#!/bin/bash
	# inputDate.sh
	# inserta fechas en todos los ficheros de un directorio

	# variables
	MAX_FILES=1000
	DIRECTORY="files"

	# generamos el directorio
	if [ ! -d "$DIRECTORY" ]; then

gdebenito / vscode settings latex files

Created June 17, 2019 08:52

gdebenito / removeDuplicatesAndFilter.js

Last active June 27, 2019 20:36

bash_history efficent cleaner

	'use-strict'
	const process = require('process')
	const fs = require('fs')

	const filename = process.argv.slice(process.argv.length - 1, process.argv.length)[0]

	const data = fs.readFileSync(filename, { encoding: 'utf-8' })

	const lines = data.split('\n').map((line) => line.trim())
	let dataWant = []

gdebenito / neo4j-docker-compose.yml

Last active March 4, 2020 16:07

Neo4j docker compose configuration with graph algorithms and apoc procedures.

gdebenito / print-variable.sh

Created November 12, 2020 09:05

	// Print variable name with the variable value
	printVariable() {
	variableName=$1;
	variableValue=$(eval "echo -n \$$1");
	echo "$variableName=$variableValue";
	}