82 lines
1.7 KiB
JavaScript
82 lines
1.7 KiB
JavaScript
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var Individual = require('individual')
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var VERSION_KEY = '1';
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var ERROR_CACHE_KEY = '__RUST_RESULT_ERROR_UUID@' + VERSION_KEY
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var OK_CACHE_KEY = '__RUST_RESULT_OK_UUID@' + VERSION_KEY
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var ERROR_UUID = Individual(ERROR_CACHE_KEY, fakeUUID('Error'))
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var OK_UUID = Individual(OK_CACHE_KEY, fakeUUID('Ok'))
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function Ok(v) {
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this.v = v
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this[OK_UUID] = true
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}
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function Err(err) {
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this.err = err
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this[ERROR_UUID] = true
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}
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function createOk(v) {
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if (isObject(v) && OK_UUID in v) {
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return v.v
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} else if (isObject(v) && ERROR_UUID in v) {
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return undefined
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} else {
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if (v === undefined) {
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throw Error('rust-result: Cannot box `undefined` in Result.Ok')
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}
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return new Ok(v)
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}
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}
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function createErr(err) {
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if (isObject(err) && ERROR_UUID in err) {
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return err.err
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} else if (isObject(err) && OK_UUID in err) {
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return undefined
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} else {
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if (!isError(err)) {
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throw Error('rust-result: Cannot box a non-error in Result.Err')
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}
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return new Err(err)
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}
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}
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function isOk(v) {
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return createOk(v) !== undefined
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}
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function isErr(err) {
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return createErr(err) !== undefined
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}
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module.exports = {
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isOk: isOk,
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Ok: createOk,
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isErr: isErr,
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Err: createErr
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}
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function fakeUUID(word) {
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return 'rust-result:' + word + ':' +
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Math.random().toString(32).slice(2) + ':' +
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Math.random().toString(32).slice(2) + ':' +
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Math.random().toString(32).slice(2) + ':' +
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Math.random().toString(32).slice(2) + ':'
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}
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function isObject(o) {
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return typeof o === 'object' && o !== null
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}
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function isError(e) {
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return isObject(e) &&
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(Object.prototype.toString.call(e) === '[object Error]' ||
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/* istanbul ignore next */ e instanceof Error)
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}
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