C++ Templates as Partial Evaluation

Todd L. Veldhuizen

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arXiv · cs/9810010

C++ Templates as Partial Evaluation

Todd L. Veldhuizen

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Abstract

This paper explores the relationship between C++ templates and partial evaluation. Templates were designed to support generic programming, but unintentionally provided the ability to perform compile-time computations and code generation. These features are completely accidental, and as a result their syntax is awkward. By recasting these features in terms of partial evaluation, a much simpler syntax can be achieved. C++ may be regarded as a two-level language in which types are first-class values. Template instantiation resembles an offline partial evaluator. This paper describes preliminary work toward a single mechanism based on Partial Evaluation which unifies generic programming, compile-time computation and code generation. The language Catat is introduced to illustrate these ideas.

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Todd L. Veldhuizen. 1998-11-02. C++ Templates as Partial Evaluation. https://arxiv.org/abs/cs/9810010

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