{"json_modified": "2015-04-12T06:23:22.171188", "slug": "Web/JavaScript/Reference/Global_Objects/undefined", "tags": [], "locale": "it", "title": "undefined", "translations": [{"title": "undefined", "url": "/en-US/docs/Web/JavaScript/Reference/Global_Objects/undefined", "tags": ["JavaScript"], "summary": "", "localization_tags": [], "locale": "en-US", "last_edit": "2015-03-27T02:31:42", "review_tags": []}, {"title": "undefined", "url": "/ja/docs/Web/JavaScript/Reference/Global_Objects/undefined", "tags": ["JavaScript"], "summary": "", "localization_tags": [], "locale": "ja", "last_edit": "2014-05-24T00:07:36", "review_tags": []}, {"title": "undefined", "url": "/es/docs/Web/JavaScript/Referencia/Objetos_globales/undefined", "tags": ["JavaScript"], "summary": "", "localization_tags": [], "locale": "es", "last_edit": "2014-11-19T12:26:22", "review_tags": []}, {"title": "undefined", "url": "/pl/docs/Web/JavaScript/Referencje/W%C5%82asno%C5%9Bci/undefined", "tags": ["Dokumentacja_JavaScript", "JavaScript", "Dokumentacje", "Wszystkie_kategorie"], "summary": "", "localization_tags": [], "locale": "pl", "last_edit": "2014-05-31T00:08:28", "review_tags": []}, {"title": "undefined", "url": "/fr/docs/Web/JavaScript/Reference/Objets_globaux/undefined", "tags": ["R\u00e9f\u00e9rence", "Reference", "R\u00e9ference", "JavaScript"], "summary": "", "localization_tags": [], "locale": "fr", "last_edit": "2015-04-07T13:38:37", "review_tags": []}, {"title": "undefined", "url": "/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/undefined", "tags": [], "summary": "", "localization_tags": [], "locale": "zh-CN", "last_edit": "2014-05-05T23:51:46", "review_tags": []}, {"title": "undefined", "url": "/ru/docs/Web/JavaScript/Reference/Global_Objects/undefined", "tags": ["JavaScript"], "summary": "", "localization_tags": [], "locale": "ru", "last_edit": "2014-11-19T12:37:14", "review_tags": []}, {"title": "undefined", "url": "/de/docs/Web/JavaScript/Reference/Global_Objects/undefined", "tags": ["JavaScript"], "summary": "", "localization_tags": [], "locale": "de", "last_edit": "2015-01-21T01:35:47", "review_tags": []}, {"title": "undefined", "url": "/ca/docs/Web/JavaScript/Referencia/Objectes_standard/undefined", "tags": [], "summary": "", "localization_tags": [], "locale": "ca", "last_edit": "2015-02-12T17:01:35", "review_tags": ["editorial"]}, {"title": "undefined", "url": "/pt-BR/docs/Web/JavaScript/Reference/Global_Objects/undefined", "tags": [], "summary": "", "localization_tags": [], "locale": "pt-BR", "last_edit": "2015-02-15T15:36:33", "review_tags": []}], "modified": "2015-04-12T06:23:20", "label": "undefined", "localization_tags": [], "url": "/it/docs/Web/JavaScript/Reference/Global_Objects/undefined", "last_edit": "2015-04-12T06:23:10", "summary": "La variabile globale\u00a0<strong><code>undefined</code></strong>\u00a0rappresenta il valore primitivo\u00a0<span style=\"font-family: Consolas, Monaco, 'Andale Mono', monospace;\"><a class=\"glossaryLink\" href=\"/en-US/docs/Glossary/Undefined\" title=\"undefined: A primitive value automatically assigned to variables that have just been declared or to formal arguments for which there are no actual arguments.\">undefined</a></span>.\u00a0\u00c8 uno dei <a class=\"glossaryLink\" href=\"/en-US/docs/Glossary/Primitive\" title=\"valori primitivi: A primitive (primitive value, primitive data type) is data that is not an object and has no methods.\">valori primitivi</a> di JavaScript.", "sections": [{"id": "Quick_Links", "title": "JavaScript Tutorials: JavaScript Guide Introduction Grammar and types Control flow and error handling Loops and iteration Functions Expressions and operators Numbers and dates Text formatting Indexed collections Keyed collections Working with objects Details of the object model Iterators and generators Meta programming Introductory JavaScript basics JavaScript technologies overview Introduction to Object Oriented JavaScript Intermediate A re-introduction to JavaScript JavaScript data structures Equality comparisons and sameness Closures Advanced Inheritance and the prototype chain Strict mode JavaScript typed arrays Memory Management Concurrency model and Event Loop References: Built-in objects Standard built-in objects Array [Translate] ArrayBuffer [Translate] Boolean [Translate] DataView [Translate] Date [Translate] Error [Translate] EvalError [Translate] Float32Array [Translate] Float64Array [Translate] Function [Translate] Generator [Translate] GeneratorFunction [Translate] Infinity Int16Array [Translate] Int32Array [Translate] Int8Array [Translate] InternalError [Translate] Intl [Translate] Intl.Collator [Translate] Intl.DateTimeFormat [Translate] Intl.NumberFormat [Translate] Iterator [Translate] JSON [Translate] Map [Translate] Math [Translate] NaN Number [Translate] Object ParallelArray [Translate] Promise [Translate] Proxy [Translate] RangeError [Translate] ReferenceError [Translate] Reflect [Translate] RegExp [Translate] Set [Translate] StopIteration [Translate] String [Translate] Symbol [Translate] SyntaxError [Translate] TypeError [Translate] TypedArray [Translate] URIError [Translate] Uint16Array [Translate] Uint32Array [Translate] Uint8Array [Translate] Uint8ClampedArray [Translate] WeakMap [Translate] WeakSet [Translate] decodeURI() [Translate] decodeURIComponent() [Translate] encodeURI() [Translate] encodeURIComponent() [Translate] escape() [Translate] La funzione eval() isFinite() [Translate] isNaN() [Translate] null [Translate] parseFloat() parseInt() undefined unescape() [Translate] uneval() [Translate] Expressions & operators Expressions and operators [Translate] Arithmetic operators [Translate] Array comprehensions [Translate] Assignment operators [Translate] Bitwise operators [Translate] Comma operator [Translate] Comparison operators [Translate] Conditional (ternary) Operator [Translate] Destructuring assignment [Translate] Expression closures [Translate] Generator comprehensions [Translate] Grouping operator [Translate] Legacy generator function expression [Translate] Logical Operators [Translate] Object initializer [Translate] Operator precedence [Translate] Property accessors [Translate] Spread operator [Translate] class expression [Translate] delete operator [Translate] function expression [Translate] function* expression [Translate] in operator [Translate] instanceof [Translate] new operator [Translate] super [Translate] this [Translate] typeof [Translate] void operator [Translate] yield [Translate] yield* [Translate] Statements & declarations Statements Legacy generator function [Translate] block [Translate] break [Translate] class [Translate] const [Translate] continue [Translate] debugger [Translate] do...while [Translate] empty [Translate] export [Translate] for [Translate] for each...in [Translate] for...in [Translate] for...of [Translate] function [Translate] function* [Translate] if...else [Translate] import [Translate] label [Translate] let return [Translate] switch [Translate] throw [Translate] try...catch [Translate] var [Translate] while [Translate] with [Translate] Functions Functions and function scope Arguments object [Translate] Arrow functions [Translate] Default parameters [Translate] Method definitions [Translate] Rest parameters [Translate] getter [Translate] setter [Translate] Classes Classes [Translate] constructor [Translate] extends [Translate] static [Translate] Misc Lexical grammar JavaScript data structures Enumerability and ownership of properties Iteration protocols Strict mode Transitioning to strict mode Template strings Deprecated features New in JavaScript New in JavaScript ECMAScript 5 support in Mozilla [Translate] ECMAScript 6 support in Mozilla ECMAScript 7 support in Mozilla [Translate] Firefox JavaScript changelog [Translate] New in JavaScript 1.1 [Translate] New in JavaScript 1.2 [Translate] New in JavaScript 1.3 [Translate] New in JavaScript 1.4 [Translate] New in JavaScript 1.5 [Translate] Novit\u00e0 in JavaScript 1.6 Novit\u00e0 in JavaScript 1.7 New in JavaScript 1.8 [Translate] New in JavaScript 1.8.1 [Translate] New in JavaScript 1.8.5 [Translate] Documentation: Useful lists All pages index Methods index Properties index Pages tagged \"JavaScript\" Contribute JavaScript doc status The MDN project"}, {"id": "Summary", "title": "Sommario"}, {"id": "Syntax", "title": "Sintassi"}, {"id": "Description", "title": "Descrizione"}, {"id": "Esempi", "title": "Esempi"}, {"id": "undefined_e_l'uguaglianza_ristretta", "title": "undefined e l'uguaglianza ristretta"}, {"id": "undefined_e_l'operatore_typeof", "title": "undefined e l'operatore typeof"}, {"id": "undefined_e_l'operatore_void", "title": "undefined e l'operatore void"}, {"id": "Specifications", "title": "Specifications"}, {"id": "Compatibilit.C3.A0_con_i_browser", "title": "Compatibilit\u00e0 con i browser"}], "id": 146939, "review_tags": []}