Span

declare const concat: {
  (that: Span): (self: Span) => Span;
  (self: Span, that: Span): Span;
};

declare const spans: (spans: Iterable<Span>) => Span;

declare const code: (value: string | Span) => Span;

declare const empty: Span;

declare const error: (value: string | Span) => Span;

declare const space: Span;

declare const strong: (value: string | Span) => Span;

declare const text: (value: string) => Span;

declare const uri: (value: string) => Span;

declare const weak: (value: string | Span) => Span;

interface Highlight {
  readonly _tag: "Highlight";
  readonly color: Color;
  readonly value: Span;
}

interface Sequence {
  readonly _tag: "Sequence";
  readonly left: Span;
  readonly right: Span;
}

type Span = Highlight | Sequence | Strong | Text | URI | Weak;

interface Strong {
  readonly _tag: "Strong";
  readonly value: Span;
}

interface Text {
  readonly _tag: "Text";
  readonly value: string;
}

interface URI {
  readonly _tag: "URI";
  readonly value: string;
}

interface Weak {
  readonly _tag: "Weak";
  readonly value: Span;
}

declare const isSequence: (self: Span) => self is Sequence;

declare const isStrong: (self: Span) => self is Strong;

declare const isText: (self: Span) => self is Text;

declare const isUri: (self: Span) => self is URI;

declare const isWeak: (self: Span) => self is Weak;