erg/doc/EN/API/operators.md

operator

infix operator

_+_|R, O, A <: Add(R, O)|(x: A, y: R) -> O

Perform addition.

_-_|R, O, S <: Sub(R, O)|(x: S, y: R) -> O

Perform subtraction.

*|R, O, M <: Mul R, O|(x: M, y: R) -> O

Perform multiplication.

/|R, O, D <: Div(R, O)|(x: D, y: R) -> O

Perform division.

infix alphabet operator

and(x: Bool, y: Bool) -> Bool

Executes the and operation.

or(x: Bool, y: Bool) -> Bool

Executes the and operation.

prefix operator

+_|T <: Num|(x: T) -> T

Same as id by default.

-_|T <: Num|(x: T) -> T.Neg

For example, Nat.-: Nat -> Neg and the return value is different.

!|T <: Immut|(x: T) -> T!

Create a mutable object from an immutable object. This operator itself is not procedural and can be used inside a function.

..|T <: Ord|(x: T) -> Range T

Creates a Range object with no lower bound at the end of x. x..x returns only x as an iterator.

..<|T <: Ord|(x: T) -> Range T

x..<x results in an empty Range object, yielding nothing as an iterator.

postfix operator

A postfix operator is called when parsing a parsing infix operator fails. That is, even if x.. returns a function, x..y is (..)(x, y) and not (x..)(y).

|T <: Ord|(x: T).. -> Range T

Creates a Range object with no upper bound starting at x.

|T <: Ord|(x: T)<.. -> Range T