Abstract Base Classes are non-instantiable classes used to define the expected behaviour of subclasses.
Questions tagged [abc]
280 questions
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Constraints(Time/area..) in Yosys and/or ABC
I am using the following basic script to synthesize simple adder design
# read design
read_verilog fulladder1.v
hierarchy -check
# high-level synthesis
proc; opt; fsm; opt; memory; opt
# low-level synthesis
techmap; opt
# map to target…
1
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2 answers
How / Is it possible to have a vector>?
Revamping some old code where I was manually handling lifetimes of a vector of raw pointers to concrete instances of an abstract base class (ABC).
So the vector's owner had a virtual dtor which manually went through and deleted the contents of the…
Mordachai
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How to incorporate type checking in an abstract base class in Python
When I define a class, I like to include type checking (using assert) of the input variables. I am now defining a 'specialized' class Rule which inherits from an abstract base class (ABC) BaseRule, similar to the following:
import abc
class…
Kurt Peek
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Standard interface for a class being an algebraic structure
Is there already any standard for an interface a Python class which is algebraic structure should implement? I want to make my code more generic.
For example, numbers and square matrices are both semigroups with multiplication and one. If they…
abukaj
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Factory class with abstractmethod
I've created a factory class called FitFunction that adds a whole bunch of stuff beyond what I've shown. The label method pretty_string is supposed to just return the string as written. When I run this file, it prints a string that is as useful as…
blalterman
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Do ABCs enforce method decorators?
I'm trying to figure out how to ensure that a method of a class inheriting from an ABC is created using the appropriate decorator. I understand (hopefully) how ABCs work in general.
from abc import ABCMeta, abstractmethod
class…
VagueAdvice
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Inconsistent implementation of collections.abc
I'm trying to understand collections.abc source code.
Let's take a look on Hashable class' __subclasshook__ implementation:
@classmethod
def __subclasshook__(cls, C):
if cls is Hashable:
for B in C.__mro__:
if "__hash__" in…
mingaleg
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Can I define a constructor in an abstract base class?
I want to write an "interface" class in C++, which is a purely virtual abstract base class.
Can I define the constructors in this interface class? A constructor cannot be a purely virtual function, but how can I then define constructors for the…
Fabian
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computational cost of ABC
I have used abc in the past, and I'd like to use them again, to enforce pure virtual like methods with @abstractmethod. This is in the context of a Python front-end to an API which users will extend frequently.
It's a bit too complicated for me to…
user349594
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1 answer
Using an abc.ABC class object in a Django template: why Django tries to instantiate it?
I want to use abc.ABC abstract class objects (not an instance) in a Django template. In these classes, I have several class methods (defined with the @classmethod decorator) that I'd like to use for displaying informations.
When I try to show the…
Dim'
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Should I use an API/ABC when designing a class used by several in C++?
I am about to add a class X that will be used by my three previously designed classes (A, B and C).
The new class X will contain data and functions for new features as well as provide services to the classes that use it to hide lower layers. The…
Tomas
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How to implicitly use the base definition of a method
I'm currently developping for python 2, and I'm trying to use abstract base classes to simulate interfaces. I have an interface, a base implementation of that interface and many subclasses that extend the base implementation. It looks like…
Jazzwave06
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Defining @property
I have problem in defining a getter by using @property in concrete class. Here is the python code:
from abc import ABCMeta, abstractproperty
class abstract(object):
__metaclass__ = ABCMeta
def __init__(self, value1):
self.v1 =…
endeavour90
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building a python abc interface with a base class that derives from a built-in type
I would like to build an interface whose base class derives from a python built-in type such a dict. To do so, I use the python abc of the standard library but when I run the following test, no exception is raised for the missing method in the…
Eurydice
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execute a terminal command using node.js
Iam trying to execute a terminal command using node.js spawn
for that am using the code
console.log(args)
var child = spawn("hark", args, {cwd: workDir});
child.stdout.on('data', function(data) {
console.log(data.toString()) …
Psl
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