April 2025
Intermediate to advanced
706 pages
22h 40m
Italian
Content preview from JavaScript: The Definitive Guide, 7a edizione
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Capitolo 2. Struttura lessicale
Questo lavoro è stato tradotto utilizzando l'AI. Siamo lieti di ricevere il tuo feedback e i tuoi commenti: translation-feedback@oreilly.com
La struttura lessicale di un linguaggio di programmazione è l'insieme delle regole elementari che specificano come si scrivono i programmi in quel linguaggio. È la sintassi di livello più basso di un linguaggio: specifica, ad esempio, l'aspetto dei nomi delle variabili, i caratteri di delimitazione dei commenti e il modo in cui un'istruzione del programma viene separata da quella successiva. Questo breve capitolo documenta la struttura lessicale di JavaScript. Copre:
-
Sensibilità alle maiuscole, spazi e interruzioni di riga
-
Commenti
-
Letterali
-
Identificatori e parole riservate
-
Unicode
-
Punto e virgola opzionale
2.1 Il testo di un programma JavaScript
JavaScript è un linguaggio sensibile alle maiuscole. Questo significa che le parole chiave del linguaggio, le variabili, i nomi delle funzioni e altri identificatori devono sempre essere digitati con una capitalizzazione coerente delle lettere. La parola chiavewhile, ad esempio, deve essere digitata "while", non "While" o "WHILE". Allo stesso modo, online, Online, OnLine e ONLINEsono quattro nomi di variabili distinti.
JavaScript ignora gli spazi che appaiono tra i token nei programmi. Per la maggior parte, JavaScript ignora anche le interruzioni di riga (ma vedi§2.6 per un'eccezione). Poiché puoi usare liberamente spazi e newline nei tuoi programmi, ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.