Relation

A static, ordered list of key-value pairs.

A relation represents a fixed set of key-value pairs. In many places in a Datalog computation we want to be sure that certain relations are not able to vary (for example, in antijoins).

@safe

struct Relation (

TupleT

) {

import std.range : isInputRange, ElementType;;

alias TT = TupleT;

TupleT[] elements;

static auto from(T values);

this(T other, ARGS args);

auto merge(T other);

bool empty();

void clear();

import std.range : isOutputRange;;

import std.format : FormatSpec;;

string toString();

void toString(Writer w, FormatSpec!Char fmt);

}

Constructors

this this(T other, ARGS args): Create an instance.

Alias This

elements

Members

Aliases

TT alias TT = TupleT: Convenient alias to retrieve the tuple type.

Functions

clear void clear(): Undocumented in source. Be warned that the author may not have intended to support it.
empty bool empty(): Undocumented in source. Be warned that the author may not have intended to support it.
merge auto merge(T other): Merges two relations into their union.
toString string toString(): Undocumented in source. Be warned that the author may not have intended to support it.
toString void toString(Writer w, FormatSpec!Char fmt): Undocumented in source. Be warned that the author may not have intended to support it.

Static functions

from auto from(T values): Convenient function to create a Relation from an array containing values with the length 2.

Variables

elements TupleT[] elements;: Sorted list of distinct tuples.