[boost] [concept] why is `requires` plural?

Subject: [boost] [concept] why is `requires` plural?
From: Lorenzo Caminiti (lorcaminiti_at_[hidden])
Date: 2010-05-25 16:27:28

Hello all,

This might be a very silly curiosity: Does anyone know why `requires`
(plural) is used to specify concept requirements?

Most keywords (all?) are not plural so I would have expexted `require`
to be used instead of `requires`. Howerver, the C++0x proposals and
ConceptC++ use `requires`. Consequently, Boost.ConceptCheck uses
BOOST_CONCEPT_REQUIRES(). Do you know why the plural form was
selected?

Thank you.

-- 
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Lorenzo