Enum Program

pub enum Program<'a, I: Instr, A> {
    Pure(Box<A>),
    Then(Box<I>, Kleisli<'a, I, I::Return, A>),
}

Represents a program, i.e. a sequence of instructions.

• The instructions are given by the type I.
• A is the return type of the program.

Variants

Pure(Box<A>)

The case Pure(a) means that the program contains no instructions and just returns the result a.

Then(Box<I>, Kleisli<'a, I, I::Return, A>)

The case Then(instr, k) means that the first instruction is instr and the remaining program is given by the kleisli arrow k.

Implementations

impl<'a, I: 'a + Instr, A> Program<'a, I, A>

pub fn and_then<B, F>(self, js: F) -> Program<'a, I, B>

where F: 'a + Fn(A) -> Program<'a, I, B>,

Appends a continuation to a program. Which means, given a function from A to Program<I, B>, passes the return value of the program to the function, and returns the resulting program.

Equivalent to the monadic >>= operator.

pub fn map<B, F>(self, f: F) -> Program<'a, I, B>

where F: 'a + Fn(A) -> B,

Modifies the return value of the program. Seen differently, it lifts a function from A to B into a function from Program<I, A> to Program<I, B>.

Equivalent to the monadic liftM.

Trait Implementations

impl<'a, I: 'a + Instr, A: Debug> Debug for Program<'a, I, A>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a, I: 'a + Instr, A: PartialEq> PartialEq for Program<'a, I, A>

fn eq(&self, other: &Program<'a, I, A>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.