bebosudo

/*
Da compilare su linux con:
gcc -o allocation_examples allocation_examples.c
oppure se si vuole usare il vecchio standard del C dell'89:
gcc --std=c89 -o allocation_examples allocation_examples.c

Si puo' poi eseguire facendo:
./allocation_examples
*/

bebosudo

Setup virtualenvwrapper on Ubuntu 16.04 or Fedora 25+

Install virtualenvwrapper, which eases the handling of Python virtualenvs (sort of Virtual Machines for Python packages).

$ pip3 install --user virtualenvwrapper

Add to your ~/.bashrc, or better, to your ~/.bash_profile:

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Create a dir to build things into:

  $ mkdir ~/stack && cd ~/stack

Download the sources (sqlite 3230100 was broken, 3220000 was used instead):

  $ wget https://www.openssl.org/source/openssl-1.1.0h.tar.gz
  $ wget https://sqlite.org/2018/sqlite-src-3220000.zip
  $ wget https://www.python.org/ftp/python/3.6.5/Python-3.6.5.tar.xz

bebosudo

from django import forms

# https://github.com/django/django/blob/master/django/forms/widgets.py
class HTML5DateWidget(forms.widgets.Input):
    input_type = 'date'
    template_name = 'django/forms/widgets/date.html'

    
    
# Example:

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# --- forms.py ---

class CSVImportForm(forms.Form):

    file = forms.FileField()
    comment = forms.CharField(max_length=50, required=False)

    
# --- utils.py ---

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Manually provide the id with:

# forms.py
class SomethingForm(...):
    id = forms.IntegerField(min_value=0)

# serializers.py
class SetIDFieldFromModel:
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

bebosudo

First of all, edit your_app_settings/settings.py and add:

INSTALLED_APPS = [
    'django.forms',  # to let django discover the built-in widgets
    ...
]

FORM_RENDERER = 'django.forms.renderers.TemplatesSetting'

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Inside your application directory, create a file your_app/signals.py.

The default project and app creator should have created a file your_app/apps.py. Inside the class used for your app, add the ready method:

class YourAppConfig(AppConfig):
    name = 'your_app'

 def ready(self):

bebosudo

If we have a model with some fields that have default values (e.g. a cost = DecimalField(default=0, null=false)), and we receive a form with that field set as None, django will complain with a NOT NULL constraint failed. We can manually set the fields of interest in the save() method of the models, or simply add this class to all the django Models, which will automatically discover and set the null fields having a default value.

from django.db.models.fields import NOT_PROVIDED

class SetModelDefaultsOnSave:
    def save(self):
        for field in self._meta.get_fields():
 if (not field.auto_created and getattr(self, field.name) is None and

bebosudo

     24046    /usr/bin/ld: /opt/cluster/spack/opt/spack/linux-centos7-x86_64/gcc-8.2.0/boost-1.68.0-xkyf5icz7yn62yjvduwrs3mfru4merj4/lib/libboost_serialization-mt.a(archive_exception.o): re
              location R_X86_64_32S against symbol `_ZTVN5boost7archive17archive_exceptionE' can not be used when making a shared object; recompile with -fPIC
     24047    /usr/bin/ld: /opt/cluster/spack/opt/spack/linux-centos7-x86_64/gcc-8.2.0/boost-1.68.0-xkyf5icz7yn62yjvduwrs3mfru4merj4/lib/libboost_serialization-mt.a(basic_archive.o): reloca
              tion R_X86_64_32 against `.rodata.str1.1' can not be used when making a shared object; recompile with -fPIC
     24048    /usr/bin/ld: /opt/cluster/spack/opt/spack/linux-centos7-x86_64/gcc-8.2.0/boost-1.68.0-xkyf5icz7yn62yjvduwrs3mfru4merj4/lib/libboost_filesystem-mt.a(operations.o): relocation R
              _X86_64_32 against `.rodata.str1.8' can not be used when making a shared object; recompile with -fPIC
     24049    /usr/bin/ld: /opt/cluster/spack/opt/spack/l