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maybe :: b -> (a -> b) -> Maybe a -> b

basement Basement.Compat.Base

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.
Examples
Basic usage:
```
>>> maybe False odd (Just 3)
True
```
```
>>> maybe False odd Nothing
False
```
Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:
```
>>> import Text.Read ( readMaybe )

>>> maybe 0 (*2) (readMaybe "5")
10

>>> maybe 0 (*2) (readMaybe "")
0
```
Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":
```
>>> maybe "" show (Just 5)
"5"

>>> maybe "" show Nothing
""
```
maybe :: b -> (a -> b) -> Maybe a -> b

basement Basement.Imports

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.
Examples
Basic usage:
```
>>> maybe False odd (Just 3)
True
```
```
>>> maybe False odd Nothing
False
```
Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:
```
>>> import Text.Read ( readMaybe )

>>> maybe 0 (*2) (readMaybe "5")
10

>>> maybe 0 (*2) (readMaybe "")
0
```
Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":
```
>>> maybe "" show (Just 5)
"5"

>>> maybe "" show Nothing
""
```
maybe :: b -> (a -> b) -> Maybe a -> b

relude Relude.Monad.Reexport

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.
Examples
Basic usage:
```
>>> maybe False odd (Just 3)
True
```
```
>>> maybe False odd Nothing
False
```
Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:
```
>>> import Text.Read ( readMaybe )

>>> maybe 0 (*2) (readMaybe "5")
10

>>> maybe 0 (*2) (readMaybe "")
0
```
Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":
```
>>> maybe "" show (Just 5)
"5"

>>> maybe "" show Nothing
""
```
maybe :: b -> (a -> b) -> Maybe a -> b

Cabal-syntax Distribution.Compat.Prelude

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.
Examples
Basic usage:
```
>>> maybe False odd (Just 3)
True
```
```
>>> maybe False odd Nothing
False
```
Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:
```
>>> import Text.Read ( readMaybe )

>>> maybe 0 (*2) (readMaybe "5")
10

>>> maybe 0 (*2) (readMaybe "")
0
```
Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":
```
>>> maybe "" show (Just 5)
"5"

>>> maybe "" show Nothing
""
```
maybe :: b -> (a -> b) -> Maybe a -> b

ghc-lib-parser GHC.Prelude.Basic

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.
Examples
Basic usage:
```
>>> maybe False odd (Just 3)
True
```
```
>>> maybe False odd Nothing
False
```
Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:
```
>>> import Text.Read ( readMaybe )

>>> maybe 0 (*2) (readMaybe "5")
10

>>> maybe 0 (*2) (readMaybe "")
0
```
Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":
```
>>> maybe "" show (Just 5)
"5"

>>> maybe "" show Nothing
""
```
maybe :: b -> (a -> b) -> Maybe a -> b

classy-prelude ClassyPrelude

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.
Examples
Basic usage:
```
>>> maybe False odd (Just 3)
True
```
```
>>> maybe False odd Nothing
False
```
Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:
```
>>> import Text.Read ( readMaybe )

>>> maybe 0 (*2) (readMaybe "5")
10

>>> maybe 0 (*2) (readMaybe "")
0
```
Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":
```
>>> maybe "" show (Just 5)
"5"

>>> maybe "" show Nothing
""
```
maybe :: b -> (a -> b) -> Maybe a -> b

numeric-prelude NumericPrelude

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.
Examples
Basic usage:
```
>>> maybe False odd (Just 3)
True
```
```
>>> maybe False odd Nothing
False
```
Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:
```
>>> import Text.Read ( readMaybe )

>>> maybe 0 (*2) (readMaybe "5")
10

>>> maybe 0 (*2) (readMaybe "")
0
```
Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":
```
>>> maybe "" show (Just 5)
"5"

>>> maybe "" show Nothing
""
```
maybe :: b -> (a -> b) -> Maybe a -> b

numeric-prelude NumericPrelude.Base

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.
Examples
Basic usage:
```
>>> maybe False odd (Just 3)
True
```
```
>>> maybe False odd Nothing
False
```
Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:
```
>>> import Text.Read ( readMaybe )

>>> maybe 0 (*2) (readMaybe "5")
10

>>> maybe 0 (*2) (readMaybe "")
0
```
Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":
```
>>> maybe "" show (Just 5)
"5"

>>> maybe "" show Nothing
""
```
maybe :: b -> (a -> b) -> Maybe a -> b

protolude Protolude

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.
Examples
Basic usage:
```
>>> maybe False odd (Just 3)
True
```
```
>>> maybe False odd Nothing
False
```
Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:
```
>>> import Text.Read ( readMaybe )

>>> maybe 0 (*2) (readMaybe "5")
10

>>> maybe 0 (*2) (readMaybe "")
0
```
Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":
```
>>> maybe "" show (Just 5)
"5"

>>> maybe "" show Nothing
""
```
maybe :: b -> (a -> b) -> Maybe a -> b

basic-prelude CorePrelude

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is Nothing, the function returns the default value. Otherwise, it applies the function to the value inside the Just and returns the result.
Examples
Basic usage:
```
>>> maybe False odd (Just 3)
True
```
```
>>> maybe False odd Nothing
False
```
Read an integer from a string using readMaybe. If we succeed, return twice the integer; that is, apply (*2) to it. If instead we fail to parse an integer, return 0 by default:
```
>>> import Text.Read ( readMaybe )

>>> maybe 0 (*2) (readMaybe "5")
10

>>> maybe 0 (*2) (readMaybe "")
0
```
Apply show to a Maybe Int. If we have Just n, we want to show the underlying Int n. But if we have Nothing, we return the empty string instead of (for example) "Nothing":
```
>>> maybe "" show (Just 5)
"5"

>>> maybe "" show Nothing
""
```

basement	Basement.Compat.Base

basement	Basement.Imports

relude	Relude.Monad.Reexport

Cabal-syntax	Distribution.Compat.Prelude

ghc-lib-parser	GHC.Prelude.Basic

classy-prelude	ClassyPrelude

numeric-prelude	NumericPrelude

numeric-prelude	NumericPrelude.Base

protolude	Protolude

basic-prelude	CorePrelude

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