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nil.ts
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nil.ts
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// Ported from js-yaml v3.13.1:
// https://github.com/nodeca/js-yaml/commit/665aadda42349dcae869f12040d9b10ef18d12da
// Copyright 2011-2015 by Vitaly Puzrin. All rights reserved. MIT license.
// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
import { Type } from "../type.ts";
function resolveYamlNull(data: string): boolean {
const max = data.length;
return (
(max === 1 && data === "~") ||
(max === 4 && (data === "null" || data === "Null" || data === "NULL"))
);
}
function constructYamlNull(): null {
return null;
}
function isNull(object: unknown): object is null {
return object === null;
}
export const nil = new Type("tag:yaml.org,2002:null", {
construct: constructYamlNull,
defaultStyle: "lowercase",
kind: "scalar",
predicate: isNull,
represent: {
canonical(): string {
return "~";
},
lowercase(): string {
return "null";
},
uppercase(): string {
return "NULL";
},
camelcase(): string {
return "Null";
},
},
resolve: resolveYamlNull,
});