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Conventions used

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "It evaluates and returns the value of expression2: expression1 ?? expression2."

A block of code is set as follows:

main() {
  var yeahDartIsGreat = "Obviously!";
  var dartIsGreat = yeahDartIsGreat ?? "I don't know";
  print(dartIsGreat); // prints Obviously!
}

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

main() {
  var someInt = 1;
  print(reflect(someInt).type.reflectedType.toString()); // prints: int
}

Any command-line input or output is written as follows:

dart code.dart

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "Also, the floating action button at the bottom end should redirect you to the Request a favor screen."

Warnings or important notes appear like this.

Tips and tricks appear like this.