Package hydra.lib.eithers

Class FromLeft

java.lang.Object

hydra.tools.PrimitiveFunction

hydra.lib.eithers.FromLeft

public class FromLeft
extends PrimitiveFunction

Extract the Left value from an Either, or return a default value.

Field Summary

Fields

Modifier and Type	Field	Description
static Name	NAME

Constructor Summary

Constructors

Constructor	Description
FromLeft()

Method Summary

Modifier and Type	Method	Description
static <A,B> A	apply(A defaultValue, Either<A,B> either)	Deprecated. Use applyLazy(Supplier, Either) instead.
static <A,B> A	applyLazy(java.util.function.Supplier<A> defaultValue, Either<A,B> either)	Lazily extract the Left value from an Either, or return a default value if it is a Right.
protected java.util.function.Function<java.util.List<Term>,java.util.function.Function<Context,java.util.function.Function<Graph,Either<InContext<Error_>,Term>>>>	implementation()	A dynamic/interpreted implementation of the function.
Name	name()	The unique name of the primitive function.
TypeScheme	type()	The datatype of the primitive function.

Methods inherited from class hydra.tools.PrimitiveFunction

term, toNative

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

NAME

public static final Name NAME

Constructor Detail

FromLeft

public FromLeft()

Method Detail

name

public Name name()

Description copied from class: PrimitiveFunction

The unique name of the primitive function.

Specified by:

name in class PrimitiveFunction

Returns:

the name of this primitive function

type

public TypeScheme type()

Description copied from class: PrimitiveFunction

The datatype of the primitive function.

Specified by:

type in class PrimitiveFunction

Returns:

the type scheme of this primitive function

implementation

protected java.util.function.Function<java.util.List<Term>,java.util.function.Function<Context,java.util.function.Function<Graph,Either<InContext<Error_>,Term>>>> implementation()

Description copied from class: PrimitiveFunction

A dynamic/interpreted implementation of the function. Subclasses implement this with Either-based logic.

Specified by:

implementation in class PrimitiveFunction

Returns:

the function implementation

apply

@Deprecated
public static <A,B> A apply(A defaultValue,
                                  Either<A,B> either)

Deprecated.

Use applyLazy(Supplier, Either) instead. Eager evaluation of the default wastes memory.

applyLazy

public static <A,B> A applyLazy(java.util.function.Supplier<A> defaultValue,
                                      Either<A,B> either)

Lazily extract the Left value from an Either, or return a default value if it is a Right. The default is only evaluated if the Either is a Right.