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How does Quines output its own source code?
The for loop on line 6 prints all ASCII characters in s until we hit the unprintable character value 1. That character represents the location of the $ character in the source code. Lines 7 and 8 print a character array declaration in C syntax that looks like {n,n,n,n,…,0} where the n are the ASCII values in integer form.
How to generate a quine string in Python?
The output is generated into the string variable quine in three parts: The raw text that comes before the $. The encoded array declaration in the form {n,n,…1,n,n,…,0}. The raw text that comes after the $. Then the Python program writes the result to quine.c.
Which is the data part of a quine?
In this linguistic analogy, the verb “to quine”, plays the role of the code, and “quine” in quotation marks plays the role of the data. We will henceforth use the words “code” and “data” a lot, to designate the code and data parts of the quine as just explained.
Is it possible to write a quine program?
Actually, it is possible, and there are some interesting ideas involved (in particular, writing a quine is not a hack that only works because the programming language has certain nice properties — it is a consequence of the general so-called “fixed-point” theorem, itself an instance of Cantor’s ubiquitous diagonal argument).
Which is an example of a quine relay?
A Quine-relay is a program written in a language that outputs a program in another language that generates in turn the starting program. A visual example is given by the featured image of this article. Also you can find here a practical example of a Quine-relays for 128 programming languages!
Which is the best way to write a quine program?
Aim of this guide is to show how to write a program that outputs its own source code with no input. This family of programs is called Quine. Why is this interesting? Well, because self-referencing stuff tends to be always interesting 🙂 There are many ways to build such programs, but the most common way is called constructive method.
How to write your first Quine program in Python?
Luckily we now know that Python provides the repr () function to return an evaluable version of a string and for the break line we can just add an escaped : And here it is your first Quine program in Python, since there is no input and the output is exactly the source code of the program!