not package:base

Boolean "not"

Type-level "not". An injective type family since 4.10.0.0.

notElem is the negation of elem.

Examples

Basic usage:

>>> 3 `notElem` []
True

>>> 3 `notElem` [1,2]
True

>>> 3 `notElem` [1,2,3,4,5]
False

For infinite structures, notElem terminates if the value exists at a finite distance from the left side of the structure:

>>> 3 `notElem` [1..]
False

>>> 3 `notElem` ([4..] ++ [3])
* Hangs forever *

Bitwise "not", also known as the binary complement.

notElem is the negation of elem.

Examples

>>> 3 `notElem` []
True

>>> 3 `notElem` [1,2]
True

>>> 3 `notElem` [1,2,3,4,5]
False

>>> 3 `notElem` [1..]
False

>>> 3 `notElem` [4..]
* Hangs forever *

Cn: Other, Not Assigned

The isNothing function returns True iff its argument is Nothing.

Examples

Basic usage:

>>> isNothing (Just 3)
False

>>> isNothing (Just ())
False

>>> isNothing Nothing
True

Only the outer constructor is taken into consideration:

>>> isNothing (Just Nothing)
False

Execute an IO action, adding the given ExceptionContext to any thrown synchronous exceptions.

Exception annotations.

ExceptionAnnotations are types which can decorate exceptions as ExceptionContext.

Render the annotation for display to the user.

Construct a singleton ExceptionContext from an ExceptionAnnotation.

Retrieve all ExceptionAnnotations of the given type from an ExceptionContext.

binotElem is the negation of bielem.

Examples

Basic usage:

>>> binotElem 42 (17, 42)
False

>>> binotElem 42 (17, 43)
True

>>> binotElem 42 (Left 42)
False

>>> binotElem 42 (Right 13)
True

>>> binotElem 42 (BiList [1..5] [1..100])
False

>>> binotElem 42 (BiList [1..5] [1..41])
True