add map3 into Apply

add ap3 into Apply

README.md

@@ -92,10 +92,26 @@ fn validate_credit_card(
  expiration: Date,
  cvv: Code,
 ) -> ValidatedNev<CreditCard, Error> {
- ValidatedNev::pure(curry3!(CreditCard::new))
- .ap(validate_number(number).into())
- .ap(validate_expiration(expiration).into())
- .ap(validate_cvv(cvv).into())
+ ValidatedNev::pure(CreditCard::new)
+ .ap3(validate_number(number).into(),
+ validate_expiration(expiration).into(),
+ validate_cvv(cvv).into())
+}
+```
+
+Alternatively, this can be done using the `map3` method:
+
+```rust
+fn validate_credit_card(
+ number: CreditCardNumber,
+ expiration: Date,
+ cvv: Code,
+) -> ValidatedNev<CreditCard, Error> {
+ let number: ValidatedNev<_,_> = validate_number(number).into();
+ let expiration = validate_expiration(expiration).into();
+ let cvv = validate_cvv(cvv).into();
+
+ Apply::map3(number, expiration, cvv, CreditCard::new)
 }
 ```
 

src/apply.rs

@@ -20,8 +20,8 @@ pub trait Apply<B>: Functor<B> + Semigroupal<B> {
  /// assert_eq!(Some("2".to_string()), f.ap(Some(2)));
  /// ```
  fn ap<A>(self, fa: Self::Target<A>) -> Self::Target<B>
- where
- Self::Param: FnOnce(A) -> B;
+  where
+  Self::Param: FnOnce(A) -> B;
 
  /// Is a binary version of [ap].
  ///
@@ -33,23 +33,45 @@ pub trait Apply<B>: Functor<B> + Semigroupal<B> {
  /// let f = Some(|x, y| x + y);
  /// assert_eq!(Some(3), f.ap2(Some(1), Some(2)));
  /// ```
+ #[inline]
  fn ap2<A, Z>(self, fa: Self::Target<A>, fb: Self::Target<B>) -> Self::Target<Z>
- where
- Self::Target<(Self::Param, B)>: Semigroupal<A, Target<A> = Self::Target<A>>
- + Higher<
- Target<(<Self::Target<(Self::Param, B)> as Higher>::Param, A)> = Self::Target<(
- <Self::Target<(Self::Param, B)> as Higher>::Param,
- A,
- )>,
- >,
- Self::Target<(<Self::Target<(Self::Param, B)> as Higher>::Param, A)>:
- Functor<Z, Target<Z> = Self::Target<Z>>,
- Self: Sized,
- Self::Param: FnOnce(A, B) -> Z,
+ where
+ Self::Param: FnOnce(A, B) -> Z,
+ Self::Target<(Self::Param, B)>: Semigroupal<A>
+ + Higher<Target<A>=Self::Target<A>>
+ + Higher<Target<((Self::Param, B), A)>=Self::Target<((Self::Param, B), A)>>,
+ Self::Target<((Self::Param, B), A)>: Functor<Z, Target<Z>=Self::Target<Z>>,
+ Self: Sized,
  {
  self.product(fb).product(fa).map(|((f, b), a)| f(a, b))
  }
 
+ /// Is a ternary version of [ap].
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use rust2fun::prelude::*;
+ ///
+ /// let f = Some(|x, y, z| x + y + z);
+ /// assert_eq!(Some(6), f.ap3(Some(1), Some(2), Some(3)));
+ /// ```
+ #[inline]
+ fn ap3<A, C, Z>(self, fa: Self::Target<A>, fb: Self::Target<B>, fc: Self::Target<C>) -> Self::Target<Z>
+ where
+ Self::Param: FnOnce(A, B, C) -> Z,
+ Self::Target<(Self::Param, B)>: Semigroupal<A>
+ + Higher<Target<A>=Self::Target<A>>
+ + Higher<Target<((Self::Param, B), A)>=Self::Target<((Self::Param, B), A)>>,
+ Self::Target<((Self::Param, B), A)>: Semigroupal<C>
+ + Higher<Target<C>=Self::Target<C>>
+ + Higher<Target<(((Self::Param, B), A), C)>=Self::Target<(((Self::Param, B), A), C)>>,
+ Self::Target<(((Self::Param, B), A), C)>: Functor<Z, Target<Z>=Self::Target<Z>>,
+ Self: Sized,
+ {
+ self.product(fb).product(fa).product(fc).map(|(((f, b), a), c)| f(a, b, c))
+ }
+
  /// Combine two effectful values into a single effectful value using a binary function.
  ///
  /// # Examples
@@ -62,15 +84,39 @@ pub trait Apply<B>: Functor<B> + Semigroupal<B> {
  /// let actual = x.map2(y, |x, y| x + y);
  /// assert_eq!(Some(3), actual);
  /// ```
+ #[inline]
  fn map2<Z, F>(self, fb: Self::Target<B>, mut f: F) -> Self::Target<Z>
- where
- F: FnMut(Self::Param, B) -> Z,
- Self::Target<(Self::Param, B)>: Functor<Z, Target<Z> = Self::Target<Z>>,
- Self: Sized,
+  where
+  F: FnMut(Self::Param, B) -> Z,
+  Self::Target<(Self::Param, B)>: Functor<Z, Target<Z>=Self::Target<Z>>,
+  Self: Sized,
  {
  self.product(fb).map(|(a, b)| f(a, b))
  }
 
+ /// Combine three effectful values into a single effectful value using a ternary function.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// use rust2fun::prelude::*;
+ ///
+ /// let x = Some(1);
+ /// let y = Some(2);
+ /// let z = Some(3);
+ /// let actual = x.map3(y, z, |x, y, z| x + y + z);
+ /// assert_eq!(Some(6), actual);
+ /// ```
+ #[inline]
+ fn map3<C, Z, F>(self, fb: Self::Target<B>, fc: Self::Target<C>, mut f: F) -> Self::Target<Z>
+ where F: FnMut(Self::Param, B, C) -> Z,
+ Self::Target<(Self::Param, B)>: Apply<C, Target<C>=Self::Target<C>>,
+ Self::Target<(Self::Param, B)>: Higher<Target<Z>=Self::Target<Z>>,
+ <Self::Target<(Self::Param, B)> as Higher>::Target<((Self::Param, B), C)>: Functor<Z, Target<Z>=Self::Target<Z>>,
+ Self: Sized, {
+ self.product(fb).map2(fc, |(a, b), c| { f(a, b, c) })
+ }
+
  /// Compose two effectful values discarding the result of the first.
  ///
  /// # Examples
@@ -85,9 +131,9 @@ pub trait Apply<B>: Functor<B> + Semigroupal<B> {
  /// ```
  #[inline]
  fn product_r(self, fb: Self::Target<B>) -> Self::Target<B>
- where
- Self::Target<(Self::Param, B)>: Functor<B, Target<B> = Self::Target<B>>,
- Self: Sized,
+  where
+  Self::Target<(Self::Param, B)>: Functor<B, Target<B>=Self::Target<B>>,
+  Self: Sized,
  {
  self.map2(fb, |_, b| b)
  }
@@ -106,9 +152,9 @@ pub trait Apply<B>: Functor<B> + Semigroupal<B> {
  /// ```
  #[inline]
  fn product_l(self, fb: Self::Target<B>) -> Self
- where
- Self::Target<(Self::Param, B)>: Functor<Self::Param, Target<Self::Param> = Self>,
- Self: Higher<Target<<Self as Higher>::Param> = Self> + Sized,
+  where
+  Self::Target<(Self::Param, B)>: Functor<Self::Param, Target<Self::Param>=Self>,
+  Self: Higher<Target<<Self as Higher>::Param>=Self> + Sized,
  {
  self.map2(fb, |a, _| a)
  }
@@ -150,8 +196,8 @@ macro_rules! apply_iter {
 impl<F, B> Apply<B> for PhantomData<F> {
  #[inline]
  fn ap<A>(self, _fa: PhantomData<A>) -> PhantomData<B>
- where
- Self::Param: FnOnce(A) -> B,
+  where
+  Self::Param: FnOnce(A) -> B,
  {
  PhantomData
  }
@@ -160,8 +206,8 @@ impl<F, B> Apply<B> for PhantomData<F> {
 impl<F, B> Apply<B> for Option<F> {
  #[inline]
  fn ap<A>(self, fa: Option<A>) -> Option<B>
- where
- Self::Param: FnOnce(A) -> B,
+  where
+  Self::Param: FnOnce(A) -> B,
  {
  self.and_then(|f| fa.map(f))
  }
@@ -170,8 +216,8 @@ impl<F, B> Apply<B> for Option<F> {
 impl<F, B, E> Apply<B> for Result<F, E> {
  #[inline]
  fn ap<A>(self, fa: Result<A, E>) -> Result<B, E>
- where
- Self::Param: FnOnce(A) -> B,
+  where
+  Self::Param: FnOnce(A) -> B,
  {
  self.and_then(|f| fa.map(f))
  }

src/data/validated/mod.rs

@@ -40,15 +40,15 @@
 //! # }
 //! # }
 //! #
-//! fn validate_number(number: CreditCardNumber) -> Validated<CreditCardNumber, Error> {
+//! fn validate_number(number: CreditCardNumber) -> ValidatedNev<CreditCardNumber, Error> {
 //! unimplemented!("Validate credit card number")
 //! }
 //!
-//! fn validate_expiration(date: Date) -> Validated<Date, Error> {
+//! fn validate_expiration(date: Date) -> ValidatedNev<Date, Error> {
 //! unimplemented!("Validate credit card expiration date")
 //! }
 //!
-//! fn validate_cvv(cvv: Code) -> Validated<Code, Error> {
+//! fn validate_cvv(cvv: Code) -> ValidatedNev<Code, Error> {
 //! unimplemented!("Validate credit card cvv")
 //! }
 //!
@@ -57,10 +57,22 @@
 //! expiration: Date,
 //! cvv: Code,
 //! ) -> ValidatedNev<CreditCard, Error> {
-//! ValidatedNev::pure(curry3!(CreditCard::new))
-//! .ap(validate_number(number).into())
-//! .ap(validate_expiration(expiration).into())
-//! .ap(validate_cvv(cvv).into())
+//! ValidatedNev::pure(CreditCard::new)
+//! .ap3(validate_number(number),
+//! validate_expiration(expiration),
+//! validate_cvv(cvv))
+//! }
+//!
+//! // Alternative implementation using `map3`:
+//! fn validate_credit_card_alt(
+//! number: CreditCardNumber,
+//! expiration: Date,
+//! cvv: Code,
+//! ) -> ValidatedNev<CreditCard, Error> {
+//! Apply::map3(validate_number(number),
+//! validate_expiration(expiration),
+//! validate_cvv(cvv),
+//! CreditCard::new)
 //! }
 //! ```
 pub use Validated::{Invalid, Valid};