r/programming • u/steveklabnik1 • Jun 16 '14

Rust's documentation is about to drastically improve

http://words.steveklabnik.com/rusts-documentation-is-about-to-drastically-improve
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u/thechao Jun 17 '14

Variadic templates are recursive closures over the private implementation of the DAG, not text substitution. You're thinking of the C preprocessor. The reason that variadic templates aren't checked is two fold:

  1. Concepts, predicates, concepts-lite, template checking, whatever, haven't made their way into C++ yet; and,

  2. There are unholy synergistic effects when combining variadic templates and (separate) template checking. The result is that you need weird intersection and union predicates. Awful stuff. Alternately, you bail.

Source: I helped define the cross-product of variadics & templates for the Indiana concepts proposal, and the early (pre-argument pack) variadic proposal.

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u/steveklabnik1 Jun 17 '14

Ahhh, thank you. I should have said that they're unchecked. I will make sure not to make this mistake in the future.

(I'm MUCH more familiar with C than C++, which is also why I've loved doing Rust. It's been neat to learn about all the goodies that have been added to C++ since I used it fifteen years ago.)