While i consider myself falling rather in the camp of the aficionados, ive met a lot more people that dont have a strong interest for it, or that even find it downright disgusting, than tmp enthusiasts. After reading these sections the reader will know how to refactor code to move points of variation from the base level to the metaprogramming level. The rst article on template metaprogramming 7 was published in 1995. Reflection support by means of template metaprogramming. This is basically thorough documentation for the boost mpl. This site is like a library, use search box in the widget to get ebook that you want. The compiler acts as an interpreter or a virtual computer that emits the instructions that make up the final program. Concepts, tools, and techniques from boost and beyond david abrahams, aleksey gurtovoy. Concepts, tools, and techniques from boost and beyond david abrahams, aleksey gurtovoy this is basically thorough documentation for the boost mpl. The use of templates can be thought of as compiletime polymorphism.
Template metaprogramming is a generic programming technique that uses extremely early binding. But most of the time, template metaprogramming is used and useful in small, isolated cases, basically to smooth out bumps and exceptional cases, to make a set of types look and behave uniformly, allowing you to use generic programming more efficiently. The if template was the rst control structure in a generic form 3 and the remaining control structures were published in 4. Metaprogramming with templates yes, the code checks whether the number is a prime number template struct isprime2. Template metaprograms can generate useful code when interpreted by the compiler, such as a massively inlined algorithm that is, an implementation of an algorithm which works for a specific input size, and has its loops unrolled. When implementing an objective function to be optimized, a user may only need to implement a few methods. Reflection support by means of template metaprogramming pdf. They are methods to achieve general, reusable code which is as fast as handcoded, and hardcoded c. Techniques for making the mpl work on vc6vc7borlandgcc2. Concepts, tools, and techniques from boost and beyond by david abrahams, aleksey gurtovoy. A complete mpl reference manual, in html and pdf form. There have been some articles dealing with template metaprogramming before over here. Consider writing a c like printf function in haskell.
Demers, a tutorial on behavioral reflection and its. I have very simple program that uses tmp,it calculates the square of a number, but it doesnt seem to. It seems really cool, make the compiler do most of the work. 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.
Generic programming and template metaprogramming are not faster than c. The performance of hardcoded algorithms, and the flexibility and reusability of general, parameterized ones. However, before you get visions in your mind of robots writing code to take over the world, understand that its actually much less intense. Among the application areas of template metaprograms are the expression templates, static interface checking, code optimization with adaption, language embedding and active libraries. With help from the excellent boost metaprogramming library, david and aleksey take tmp from the laboratory to the workplace with readable prose and practical examples, showing that compiletime stl is as able as its runtime counterpart. An introduction to metaprogramming for scientific computing dr conrad sanderson senior research scientist version 1. An introduction to template metaprogramming barney dellar software team lead. A metaprogram is a program that generates or manipulates program code. I was motivated to write this after i read eric nieblers thoughtprovoking tiny metaprogramming library article. This post starts a series of articles following the contrived and tortuous path down insanity lane. E book the boost c libraries download ebook pdf, epub. Boost library documentation template metaprogramming. Tmp doesnt have branching, so we use specialization.
Some programs or libraries obfuscate the underlying integer type of. The library brings together important abstractions from the generic and functional programming worlds to build a powerful and easytouse toolset which makes template. Template metaprogramming is both a curiosity and a powerful optimisation method. Algorithms are expressed using template recursion as a looping construct and class template specialization as a conditional construct. The output of these templates include compiletime constants, data structures, and complete functions. This is typical of cbased libraries, where parameters are. Dabei kommen vor allem templates zum einsatz in diesem fall spricht man. A macro is a piece of code that executes at compile time and either performs textual manipulation of code tobe compiled e.
It can, for the most part, be considered to be programming with types in that, largely, the. Click download or read online button to get e book the boost c libraries book now. An introduction to template metaprogramming barney dellar software team lead toshiba medical visualisation systems. Template metaprogramming is turingcomplete, meaning that any computation expressible by a computer program can be computed, in some form, by a template metaprogram. Some of the advanced template features utilized by libraries such as boost and stlsoft, and implementations of the stl itself, for template metaprogramming explicit or partial specialization, default template arguments, template nontype arguments, template template arguments. Technically metaprogramming is code that writes code. Template metaprogramming can be used to automatically produce the right type.
Template metaprograms consist of class templates operating on numbers andor types as data. In theory, any computable problem can be solved at compile time without ever executing compiled code. Things like template, which look really weird but behave in an even more bizarre way. When c was developed, maths libraries implemented functions such as square. The overwhelming majority of generic libraries, including the original version of stl, were written without language support for concepts and used without enforcement mechanisms.
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