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Daniel Gonçalves danielgoncalves

  • Base4 Sistemas
  • Catanduva/SP
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danielgoncalves /
Last active Oct 9, 2020 — forked from jsbueno/
Lazy sorter - an iterator that yields items in sorted order, lazily
import random
import string
from lazyquicksort import lazy_sort
def chars(length):
options = string.ascii_lowercase
return ''.join([random.choice(options) for i in range(length)])
danielgoncalves /
Last active Jul 8, 2020
PyESCPOS sandbox script
# -*- coding: utf-8 -*-
# Requires
# Have a look at
from __future__ import unicode_literals
from __future__ import print_function
import logging.config
from escpos import showcase
from escpos.conn.usb import USBConnection
danielgoncalves /
Created Feb 21, 2020 — forked from emmanueltissera/
Generate a git patch for a specific commit

Creating the patch

git format-patch -1 <sha>
git format-patch -1 HEAD

Applying the patch

git apply --stat file.patch # show stats.
git apply --check file.patch # check for error before applying

danielgoncalves /
Created Jan 22, 2020 — forked from Kartones/
PostgreSQL command line cheatsheet


Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

  • -E: will describe the underlaying queries of the \ commands (cool for learning!)
  • -l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)
View singleton_way_to_go.dart
// (!) This implementation seems to work;
// Trying this in DartPad results in "s = false" and "f = true" as expected.
// This was taken from
class FooBar {
static final FooBar _instance = new FooBar._internal();
factory FooBar() => _instance;
FooBar._internal() {
// initialization logic here
danielgoncalves /
Created Apr 23, 2018 — forked from luxinyan/
Generate barcode with reportlab.
from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import A4
from reportlab.lib.units import mm
#I"ll be generating code39 barcodes, others are available
from import code39
# generate a canvas (A4 in this case, size doesn"t really matter)
# create a barcode object
# (is not displayed yet)
danielgoncalves /
Last active Nov 23, 2017 — forked from dankrause/
Simple socket IPC in python
# Copyright 2017 Dan Krause
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
danielgoncalves /
Created Jan 11, 2017 — forked from mkropat/
Python wrapper around the SHGetKnownFolderPath Windows Shell function
import ctypes, sys
from ctypes import windll, wintypes
from uuid import UUID
class GUID(ctypes.Structure): # [1]
_fields_ = [
("Data1", wintypes.DWORD),
("Data2", wintypes.WORD),
("Data3", wintypes.WORD),
("Data4", wintypes.BYTE * 8)
danielgoncalves /
Last active Dec 13, 2015
Minimalist tool to search and list occurrences of unique exceptions in log files. The exceptions should be logged using the `exception` method.
# -*- coding: utf-8 -*-
# is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
# is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
danielgoncalves /
Created Sep 5, 2011
Validate an IPv4 address.
def is_ip(value):
"""IP simple validation in response to blog post"""
bytes = [int(e) for e in value.split('.') if 0 <= int(e) <= 255)]
except ValueError:
return False
return len(bytes) == 4