Metaprogramming elixir write less code, get more done and have fun. The output of these templates include compiletime constants, data structures, and complete functions. The ability of a program to manipulate as data something representing the state of a program during its own execution. One use of templates is for mathematical structures.
The book deals with language aspects, design patterns, examples and applications seen as case studies. In smalltalk, it is about hacking doesnotunderstand. Metaprogrammingits a term that may come across as abstract, nebulous, or just downright scary. A collection of hopefully relevant links with some minimal explanations, which would allow the reader to see some examples and applications of metaprogramming in mathematica, or at least examples of what i consider metaprogramming in mathematica. The introduction to template metaprogramming in the guidelines ends.
It allows even inexperienced programmers to perform compile. Net is designed to help readers understand the basic concepts, advantages and potential pitfalls of metaprogramming. In some cases, this allows programmers to minimize the number of lines of code to express a solution hence reducing development time. An example of this is an sqrt function that takes an integer i. The c api is designed for three kinds of customers. Sometimes it will be useful to get the dimensionality tensor. Too much cleverness in programming makes designs more complicated, code more fragile, learning curves steeper, and worst of all, it makes debugging harder. Boost libraries discussed in this book that are not yet part of an official release. So metaclasses create classes, and classes create instances. Only a metaprogramming api provides a natural path for a code modification system. It introduces core concepts like code generation and application composition in clear, easytofollow language, and then it takes you on a deep dive. Contribute to akimboykometaprogramming development by creating an account on github. Starting off the list for examples of metaprogramming is monkey patching.
These functions can be used in both taichi kernels and python scripts. Lilly, refers to the hardware of the human anatomy. That doesnt work if the language doesnt support metaprogramming well. While this approach lets us avoid a heavyweight library for building abstract syntax. Template metaprogramming tmp is a metaprogramming technique in which templates are used by a compiler to generate temporary source code, which is merged by the compiler with the rest of the source code and then compiled. Great introduction to c metaprogramming by simon tatham can be found here. This book avoids abstract theory and instead teaches you solid practices youll find useful immediately. Metaprogramming is frowned on in python and considered unpythonic. Macros make metaprogramming possible and define the. Typedirected metaprogramming in rust will crichton. This article describes a technique for using the c preprocessor to implement a form of metaprogramming in c, allowing a programmer to define custom looping and control constructions which behave syntactically like c s own for, while and if. Metaprogramming in c is the art of creating new language constructs, typically using macros. You can call this at compile time with something like adder result, which will be expanded at compile time and act exactly like a literal 3 in your program branching. Api transitionsusability componentspecific optimization all kinds of instrumentation.
Copyright c 20, decorators with args 47 from functools import wraps def debugprefix. This would include the brain, internal organs, and other human organ systems such as cardiovascular, digestive, endocrine, immune, integumentary, lymphatic, muscular, nervous, reproductive, respiratory, skeletal, and urinary systems. Metaprogramming with templates yes, the code checks whether the number is a prime number template struct isprime2 static const int resisprime2 res. The c api known as vix is an api that lets customers write scripts and programs to manipulate virtual machines. A complete mpl reference manual, in html and pdf form. Being late to the metaprogramming party, i make no claim of having invented the techniques in this article. A conditional branch can be constructed by writing two alternative specialisations of a template class. Michele and david feel, in part, responsible for some excesses of cleverness in python metaclasses. What weve done now is program a little function or subroutine that is evaluated compiletime, using tmp. This makes it possible to create a template which calculates a value at return time, a value which can then be used as a constant in the rest of the program. Efficient algorithms for membership testing, random access, and retrieval by key. With a metaprogramming api, precompiled shader programs could still be used in the traditional manner simply by. Youll explore plenty of realworld examples that reinforce key concepts. Monkey patching is an object oriented programming technique that allows developers to.
An introduction to metaprogramming for scientific computing dr conrad sanderson senior research scientist version 1. This is a function that adds its two parameters and stores the result in the result enum member. The compiler can usefully do metaprogramming thats following metaprogramming directives i wrote at a variety of stages, early, middle, late. Now expanding about the use of templates for that purpose. Another more recent library that shows it can be done in python is macropy. Metaprogramming is a programming technique in which computer programs have the ability to treat other programs as their data. It means that a program can be designed to read, generate, analyze or transform other programs, and even modify itself while running. Caveat i decided to do this talk after getting thoroughly lost on the recent talk on sfinae. Jonathan cohen nvidia research gtc, san jose convention center, ca sept. Metaprogramming is a technique that consists in writing programs that treat other. Metaprogramming in commonlisp is about the metaobjectprotocol. A metaprogram is a program that generates or manipulates program code. What matters is that metaprogramming is about manipulating the code i wrote, using additional code i wrote, to produce the final code that executes.
It is highlevel, easy to use, and practical for both scripters and application programmers. A traditional program is mainly code that manipulates a data structure and produces output. Hana or boostmpl if you wish, can i build a list of types at compile time or static. This is typical of cbased libraries, where parameters are. That is the subset of metaprogramming called generativeprogramming.
I dont know who wrote the above, but i think it is wrong. The only widely known example of metaprogramming in python was an implementation of a goto and comefrom keyword done as an aprilfools joke. Reflection support by means of template metaprogramming. Unification of compiletime and runtime metaprogramming.
Most people insist on trying to metaprogram from inside their favorite language. What are some advanced uses of template metaprogramming in. The goal is to offer a different perspective on metaprogramming, how we can approach it, and the kind of use cases it can address. The biocomputer has stored program properties, and self. It introduces core concepts in clear, easytofollow language and then it takes you on a deep dive into the tools and techniques youll use to implement them in your. John c lilly, and thank you coincidence control publishing for releasing this edition unabridged, straight from johns biocomputer to yours. Programming and metaprogramming in the human biocomputer. A way around this is to do metaprogramming from outside the language, using program transformation tools. Developers can use json formats to parse responses and obtain urls of generated files. An introduction to template metaprogramming barney dellar software team lead toshiba medical visualisation systems. Therefore, i call this projecttechnique template metaprogramming programming. Yes, its a weird name, but its a powerful and dangerous tool. Otherwise, you can treat this as an example of what typedirected metaprogramming could look like in a brighter future where these apis are stable. In this article, they attempt to make amends, by helping programmers eschew cleverness.
Developers can sign up with an api key to make calls that will display json responses in return. If you are a rust metaprogramming compilerhacking fanatic like me, then the specifics will help you understand how to actually use the compilers api. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Metaprogramming in the host language yacc is an example. Metaprogramming python 3 patterns, recipes and idioms.
Template metaprogramming tmp is a metaprogramming technique in which templates are. Net is a practical introduction to the use of metaprogramming to improve the performance and maintainability of your code. Learn why metaprogramming is necessary and look at some of the. In order to explain metaprogramming, let me explain a few basic concepts first. In this session, well break down what metaprogramming is and. The use of templates can be thought of as compiletime execution. In a small summary report written for the national institute of mental health, entitled programming and metaprogramming in the human biocomputer 19661967, lilly lends his unique insight after five years of research combining lsd25 and sensory deprivation to alter behavioral and cognitive patterns in. Metaprogramming is the writing of computer programs that write or manipulate other programs or themselves as their data, or that do part of the work at compile time that would otherwise be done at runtime. Anything thats wrong is the fault of a blog migration, everything thats right is because the author of this article spent countless hours researching this topic. After so many years and blog migrations, this article might be broken or outdated.
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