Definitions

from The Century Dictionary.

  • noun In mathematics, a function which stands in the same relation to the primitive function from which it is derived as any of its linear transforms to an inversely derived transform of its primitive.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • adjective category theory which reverses composition
  • adjective computing, programming Using or relating to contravariance.

Etymologies

Sorry, no etymologies found.

Support

Help support Wordnik (and make this page ad-free) by adopting the word contravariant.

Examples

  • The nice thing about all of this is that as a user of generic types declared to be co- and/or contravariant in certain type parameters, you don't need to worry about it at all

    B# .NET Technical Community Homepage bart 2010

  • What this says is that Inject requires T to be contravariant (available for input positions) but it's declared to be covariant.

    B# .NET Technical Community Homepage bart 2010

  • The nice thing about all of this is that as a user of generic types declared to be co- and/or contravariant in certain type parameters, you don't need to worry about it at all

    B# .NET Technical Community Homepage bart 2010

  • The reason for this is a combination of Java's covariant arrays, the natural subtypes among function types (they are covariant on return type and contravariant on argument types), exception checking, and the erasure implementation of generics.

    Blog Posts editor 2010

  • In fact, this even correctly follows the expected change in variance, since Func is covariant in T and Action is contravariant in T.

    B# .NET Technical Community Homepage bart 2010

  • What this says is that Inject requires T to be contravariant (available for input positions) but it's declared to be covariant.

    B# .NET Technical Community Homepage bart 2010

  • Any nonvariant type will compile (absent other problems), but you can always change a nonvariant type parameter into a covariant or contravariant one without breaking any client code.

    Hottest News Articles 2009

  • If a library designer tries to make something covariant or contravariant that isn't by nature covariant or contravariant, the program won't compile.

    Hottest News Articles 2009

  • Any nonvariant type will compile (absent other problems), but you can always change a nonvariant type parameter into a covariant or contravariant one without breaking any client code.

    Hottest News Articles 2009

  • If a library designer tries to make something covariant or contravariant that isn't by nature covariant or contravariant, the program won't compile.

    Hottest News Articles 2009

Comments

Log in or sign up to get involved in the conversation. It's quick and easy.

  • Man, not too many category theory fans on here :)

    January 3, 2007

  • we're all into string theory

    November 7, 2009