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The dataset generation failed
Error code: DatasetGenerationError
Exception: IndexError
Message: list index out of range
Traceback: Traceback (most recent call last):
File "/usr/local/lib/python3.12/site-packages/datasets/builder.py", line 1898, in _prepare_split_single
original_shard_lengths[original_shard_id] += len(table)
~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^
IndexError: list index out of range
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/src/services/worker/src/worker/job_runners/config/parquet_and_info.py", line 1347, in compute_config_parquet_and_info_response
parquet_operations = convert_to_parquet(builder)
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/src/services/worker/src/worker/job_runners/config/parquet_and_info.py", line 980, in convert_to_parquet
builder.download_and_prepare(
File "/usr/local/lib/python3.12/site-packages/datasets/builder.py", line 884, in download_and_prepare
self._download_and_prepare(
File "/usr/local/lib/python3.12/site-packages/datasets/builder.py", line 947, in _download_and_prepare
self._prepare_split(split_generator, **prepare_split_kwargs)
File "/usr/local/lib/python3.12/site-packages/datasets/builder.py", line 1736, in _prepare_split
for job_id, done, content in self._prepare_split_single(
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/datasets/builder.py", line 1919, in _prepare_split_single
raise DatasetGenerationError("An error occurred while generating the dataset") from e
datasets.exceptions.DatasetGenerationError: An error occurred while generating the datasetNeed help to make the dataset viewer work? Make sure to review how to configure the dataset viewer, and open a discussion for direct support.
url string | title string | content string | code_snippets list | language string | source string | token_count int64 |
|---|---|---|---|---|---|---|
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/parse/contributors.txt | null | # Contributors by commit history
https://github.com/mdn/content/commits/main/files/en-us/web/javascript/reference/global_objects/json/parse/index.md
# Original Wiki contributors
mfuji09
SebastianSimon
wbamberg
hikigaya58
fscholz
nakhodkiin
anonyco
SphinxKnight
Richienb
alattalatta
schalkneethling
whirr.click
bartoloca... | [] | JavaScript | mdn | 142 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/Symbol.hasInstance | Function.prototype[Symbol.hasInstance]() | Function.prototype[Symbol.hasInstance]()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2017.
The [Symbol.hasInstance]()
method of Function
instances specifies the default procedure for determining if a const... | [
"func[Symbol.hasInstance](value)\n",
"class Foo {}\nconst foo = new Foo();\nconsole.log(foo instanceof Foo === Foo[Symbol.hasInstance](foo)); // true\n",
"class Foo {\n static [Symbol.hasInstance](value) {\n // A custom implementation\n return false;\n }\n}\n\nconst foo = new Foo();\nconsole.log(foo ins... | JavaScript | mdn | 752 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat/formatToParts | Intl.ListFormat.prototype.formatToParts() | Intl.ListFormat.prototype.formatToParts()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2021.
The formatToParts()
method of Intl.ListFormat
instances returns an array of objects representing each part of the... | [
"const vehicles = [\"Motorcycle\", \"Bus\", \"Car\"];\n\nconst formatterEn = new Intl.ListFormat(\"en\", {\n style: \"long\",\n type: \"conjunction\",\n});\n\nconst formatterFr = new Intl.ListFormat(\"fr\", {\n style: \"long\",\n type: \"conjunction\",\n});\n\nconst partValuesEn = formatterEn.formatToParts(vehi... | JavaScript | mdn | 795 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString | Date.prototype.toISOString() | Date.prototype.toISOString()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The toISOString()
method of Date
instances returns a string representing this date in the date time string format, a simplified... | [
"const event = new Date(\"05 October 2011 14:48 UTC\");\nconsole.log(event.toString());\n// Expected output: \"Wed Oct 05 2011 16:48:00 GMT+0200 (CEST)\"\n// Note: your timezone may vary\n\nconsole.log(event.toISOString());\n// Expected output: \"2011-10-05T14:48:00.000Z\"\n",
"toISOString()\n",
"const d = new ... | JavaScript | mdn | 433 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Subtraction_assignment | Subtraction assignment (-=) | Subtraction assignment (-=)
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The subtraction assignment (-=
) operator performs subtraction on the two operands and assigns the result to the left operand.
T... | [
"let a = 2;\n\nconsole.log((a -= 3));\n// Expected output: -1\n\nconsole.log((a -= \"Hello\"));\n// Expected output: NaN\n",
"x -= y\n",
"let bar = 5;\n\nbar -= 2; // 3\n",
"bar -= \"foo\"; // NaN\n",
"let foo = 3n;\nfoo -= 2n; // 1n\nfoo -= 1; // TypeError: Cannot mix BigInt and other types, use explicit c... | JavaScript | mdn | 312 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/NumberFormat/NumberFormat | Intl.NumberFormat() constructor | Intl.NumberFormat() constructor
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2017.
The Intl.NumberFormat()
constructor creates Intl.NumberFormat
objects.
Try it
const number = 123456.789;
console.log(
n... | [
"const number = 123456.789;\n\nconsole.log(\n new Intl.NumberFormat(\"de-DE\", { style: \"currency\", currency: \"EUR\" }).format(\n number,\n ),\n);\n// Expected output: \"123.456,79 €\"\n\n// The Japanese yen doesn't use a minor unit\nconsole.log(\n new Intl.NumberFormat(\"ja-JP\", { style: \"currency\", cu... | JavaScript | mdn | 9,880 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DurationFormat | Intl.DurationFormat | Intl.DurationFormat
Baseline
2025
Newly available
Since March 2025, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.
The Intl.DurationFormat
object enables language-sensitive duration formatting.
Constructor
Intl.DurationFormat()
-
Creates a ne... | [
"const duration = {\n hours: 1,\n minutes: 46,\n seconds: 40,\n};\n\n// With style set to \"long\" and locale \"fr-FR\"\nnew Intl.DurationFormat(\"fr-FR\", { style: \"long\" }).format(duration);\n// \"1 heure, 46 minutes et 40 secondes\"\n\n// With style set to \"short\" and locale \"en\"\nnew Intl.DurationForma... | JavaScript | mdn | 697 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/toString | Number.prototype.toString() | Number.prototype.toString()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The toString()
method of Number
values returns a string representing this number value.
Try it
function hexColor(c) {
if (c < 25... | [
"function hexColor(c) {\n if (c < 256) {\n return Math.abs(c).toString(16);\n }\n return 0;\n}\n\nconsole.log(hexColor(233));\n// Expected output: \"e9\"\n\nconsole.log(hexColor(\"11\"));\n// Expected output: \"b\"\n",
"toString()\ntoString(radix)\n",
"console.log((10 ** 21.5).toString()); // \"3.16227766... | JavaScript | mdn | 1,506 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/constructor | Object.prototype.constructor | Object.prototype.constructor
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The constructor
data property of an Object
instance returns a reference to the constructor function that created the instance o... | [
"const o1 = {};\no1.constructor === Object; // true\n\nconst o2 = new Object();\no2.constructor === Object; // true\n\nconst a1 = [];\na1.constructor === Array; // true\n\nconst a2 = new Array();\na2.constructor === Array; // true\n\nconst n = 3;\nn.constructor === Number; // true\n",
"const o = new TypeError(); ... | JavaScript | mdn | 3,724 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/Symbol.toPrimitive | Date.prototype[Symbol.toPrimitive]() | Date.prototype[Symbol.toPrimitive]()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2017.
The [Symbol.toPrimitive]()
method of Date
instances returns a primitive value representing this date. It may either be... | [
"// Depending on timezone, your results will vary\nconst date = new Date(\"20 December 2019 14:48\");\n\nconsole.log(date[Symbol.toPrimitive](\"string\"));\n// Expected output: \"Fri Dec 20 2019 14:48:00 GMT+0530 (India Standard Time)\"\n\nconsole.log(date[Symbol.toPrimitive](\"number\"));\n// Expected output: 1576... | JavaScript | mdn | 832 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Temporal/Duration/seconds | Temporal.Duration.prototype.seconds | Temporal.Duration.prototype.seconds
Limited availability
This feature is not Baseline because it does not work in some of the most widely-used browsers.
The seconds
accessor property of Temporal.Duration
instances returns an integer representing the number of seconds in the duration.
Unless the duration is balanced, yo... | [
"const d1 = Temporal.Duration.from({ minutes: 1, seconds: 30 });\nconst d2 = Temporal.Duration.from({ minutes: -1, seconds: -30 });\nconst d3 = Temporal.Duration.from({ minutes: 1 });\nconst d4 = Temporal.Duration.from({ seconds: 60 });\n\nconsole.log(d1.seconds); // 30\nconsole.log(d2.seconds); // -30\nconsole.log... | JavaScript | mdn | 555 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DateTimeFormat | Intl.DateTimeFormat | Intl.DateTimeFormat
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2017.
The Intl.DateTimeFormat
object enables language-sensitive date and time formatting.
Try it
const date = new Date(Date.UTC(2020, 11,... | [
"const date = new Date(Date.UTC(2020, 11, 20, 3, 23, 16, 738));\n// Results below assume UTC timezone - your results may vary\n\n// Specify default date formatting for language (locale)\nconsole.log(new Intl.DateTimeFormat(\"en-US\").format(date));\n// Expected output: \"12/20/2020\"\n\n// Specify default date form... | JavaScript | mdn | 2,914 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Execution_model | JavaScript execution model | JavaScript execution model
This page introduces the basic infrastructure of the JavaScript runtime environment. The model is largely theoretical and abstract, without any platform-specific or implementation-specific details. Modern JavaScript engines heavily optimize the described semantics.
This page is a reference. I... | [
"function foo(b) {\n const a = 10;\n return a + b + 11;\n}\n\nfunction bar(x) {\n const y = 3;\n return foo(x * y);\n}\n\nconst baz = bar(7); // assigns 42 to baz\n",
"function* gen() {\n console.log(1);\n yield;\n console.log(2);\n}\n\nconst g = gen();\ng.next(); // logs 1\ng.next(); // logs 2\n",
"func... | JavaScript | mdn | 5,176 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/supportedValuesOf | Intl.supportedValuesOf() | Intl.supportedValuesOf()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since March 2022.
The Intl.supportedValuesOf()
static method returns an array containing the supported calendar, collation, currency, numbering syst... | [
"console.log(Intl.supportedValuesOf(\"calendar\"));\nconsole.log(Intl.supportedValuesOf(\"collation\"));\nconsole.log(Intl.supportedValuesOf(\"currency\"));\nconsole.log(Intl.supportedValuesOf(\"numberingSystem\"));\nconsole.log(Intl.supportedValuesOf(\"timeZone\"));\nconsole.log(Intl.supportedValuesOf(\"unit\"));\... | JavaScript | mdn | 5,609 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/PluralRules/contributors.txt | null | # Contributors by commit history
https://github.com/mdn/content/commits/main/files/en-us/web/javascript/reference/global_objects/intl/pluralrules/index.md
# Original Wiki contributors
longlho
mfuji09
fscholz
sideshowbarker
battaglr
shvaikalesh
jpmedley
Tagir-A
| [] | JavaScript | mdn | 65 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/POSITIVE_INFINITY | Number.POSITIVE_INFINITY | Number.POSITIVE_INFINITY
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The Number.POSITIVE_INFINITY
static data property represents the positive Infinity value.
Try it
function checkNumber(bigNumber) {
... | [
"function checkNumber(bigNumber) {\n if (bigNumber === Number.POSITIVE_INFINITY) {\n return \"Process number as Infinity\";\n }\n return bigNumber;\n}\n\nconsole.log(checkNumber(Number.MAX_VALUE));\n// Expected output: 1.7976931348623157e+308\n\nconsole.log(checkNumber(Number.MAX_VALUE * 2));\n// Expected out... | JavaScript | mdn | 762 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining | Optional chaining (?.) | Optional chaining (?.)
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2020.
The optional chaining (?.
) operator accesses an object's property or calls a function. If the object accessed or function called usi... | [
"const adventurer = {\n name: \"Alice\",\n cat: {\n name: \"Dinah\",\n },\n};\n\nconst dogName = adventurer.dog?.name;\nconsole.log(dogName);\n// Expected output: undefined\n\nconsole.log(adventurer.someNonExistentMethod?.());\n// Expected output: undefined\n",
"obj?.prop\nobj?.[expr]\nfunc?.(args)\n",
"c... | JavaScript | mdn | 2,871 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DateTimeFormat/DateTimeFormat | Intl.DateTimeFormat() constructor | Intl.DateTimeFormat() constructor
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2017.
The Intl.DateTimeFormat()
constructor creates Intl.DateTimeFormat
objects.
Try it
const date = new Date(Date.UTC(2020... | [
"const date = new Date(Date.UTC(2020, 11, 20, 3, 23, 16, 738));\n// Results below assume UTC timezone - your results may vary\n\n// Specify default date formatting for language (locale)\nconsole.log(new Intl.DateTimeFormat(\"en-US\").format(date));\n// Expected output: \"12/20/2020\"\n\n// Specify default date form... | JavaScript | mdn | 4,448 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Temporal/Now/plainDateISO | Temporal.Now.plainDateISO() | Temporal.Now.plainDateISO()
Limited availability
This feature is not Baseline because it does not work in some of the most widely-used browsers.
The Temporal.Now.plainDateISO()
static method returns the current date as a Temporal.PlainDate
object, in the ISO 8601 calendar and the specified time zone.
Syntax
Temporal.No... | [
"Temporal.Now.plainDateISO()\nTemporal.Now.plainDateISO(timeZone)\n",
"// The current date in the system's time zone\nconst date = Temporal.Now.plainDateISO();\nconsole.log(date); // e.g.: 2021-10-01\n\n// The current date in the \"America/New_York\" time zone\nconst dateInNewYork = Temporal.Now.plainDateISO(\"Am... | JavaScript | mdn | 437 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Strict_inequality | Strict inequality (!==) | Strict inequality (!==)
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The strict inequality (!==
) operator checks whether its two operands are
not equal, returning a Boolean result. Unlike the inequali... | [
"console.log(1 !== 1);\n// Expected output: false\n\nconsole.log(\"hello\" !== \"hello\");\n// Expected output: false\n\nconsole.log(\"1\" !== 1);\n// Expected output: true\n\nconsole.log(0 !== false);\n// Expected output: true\n",
"x !== y\n",
"x !== y;\n\n!(x === y);\n",
"3 !== \"3\"; // true\n",
"\"hello... | JavaScript | mdn | 591 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol/description/contributors.txt | null | # Contributors by commit history
https://github.com/mdn/content/commits/main/files/en-us/web/javascript/reference/global_objects/symbol/description/index.md
# Original Wiki contributors
wbamberg
fscholz
ddbeck
sideshowbarker
ExE-Boss
turtlemaster19
LJHarb
| [] | JavaScript | mdn | 64 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt/asUintN/contributors.txt | null | # Contributors by commit history
https://github.com/mdn/content/commits/main/files/en-us/web/javascript/reference/global_objects/bigint/asuintn/index.md
# Original Wiki contributors
fscholz
mfuji09
wbamberg
AnyhowStep
sideshowbarker
ExE-Boss
| [] | JavaScript | mdn | 60 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Lexical_grammar/contributors.txt | null | # Contributors by commit history
https://github.com/mdn/content/commits/main/files/en-us/web/javascript/reference/lexical_grammar/index.md
# Original Wiki contributors
iwhoisrishabh
hinell
wbamberg
fscholz
lucaswerkmeister
neverRare
LeonFrempong
mfuji09
Aljullu
rwaldron
jinbeomhong
alattalatta
Nux
chrisdavidmills
iren... | [] | JavaScript | mdn | 141 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DurationFormat/format/contributors.txt | null | # Contributors by commit history
https://github.com/mdn/content/commits/main/files/en-us/web/javascript/reference/global_objects/intl/durationformat/format/index.md
| [] | JavaScript | mdn | 41 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Key_not_weakly_held/contributors.txt | null | # Contributors by commit history
https://github.com/mdn/content/commits/main/files/en-us/web/javascript/reference/errors/key_not_weakly_held/index.md
| [] | JavaScript | mdn | 37 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Malformed_URI | URIError: malformed URI sequence | URIError: malformed URI sequence
The JavaScript exception "malformed URI sequence" occurs when URI encoding or decoding wasn't successful.
Message
URIError: URI malformed (V8-based) URIError: malformed URI sequence (Firefox) URIError: String contained an illegal UTF-16 sequence. (Safari)
Error type
URIError
What went w... | [
"encodeURI(\"\\uD800\");\n// \"URIError: malformed URI sequence\"\n\nencodeURI(\"\\uDFFF\");\n// \"URIError: malformed URI sequence\"\n",
"encodeURI(\"\\uD800\\uDFFF\");\n// \"%F0%90%8F%BF\"\n",
"decodeURIComponent(\"%E0%A4%A\");\n// \"URIError: malformed URI sequence\"\n",
"decodeURIComponent(\"JavaScript_%D... | JavaScript | mdn | 440 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/length | Function: length | Function: length
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The length
data property of a Function
instance indicates the number of parameters expected by the function.
Try it
function func1() {}
fun... | [
"function func1() {}\n\nfunction func2(a, b) {}\n\nconsole.log(func1.length);\n// Expected output: 0\n\nconsole.log(func2.length);\n// Expected output: 2\n",
"console.log(Function.length); // 1\n\nconsole.log((() => {}).length); // 0\nconsole.log(((a) => {}).length); // 1\nconsole.log(((a, b) => {}).length); // 2... | JavaScript | mdn | 611 |
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Cant_delete | TypeError: property "x" is non-configurable and can't be deleted | TypeError: property "x" is non-configurable and can't be deleted
The JavaScript exception "property is non-configurable and can't be deleted" occurs when it was attempted to delete a property, but that property is non-configurable.
Message
TypeError: Cannot delete property 'x' of #<Object> (V8-based) TypeError: propert... | [
"\"use strict\";\nconst obj = Object.freeze({ name: \"Elsa\", score: 157 });\ndelete obj.score; // TypeError\n",
"\"use strict\";\nconst obj = {};\nObject.defineProperty(obj, \"foo\", { value: 2, configurable: false });\ndelete obj.foo; // TypeError\n",
"\"use strict\";\nconst frozenArray = Object.freeze([0, 1,... | JavaScript | mdn | 461 |
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