Episode 6: Exploring Dart: Built-in Types

Season 2: Exploring Dart

Diving Deep into Dart's Built-in Types

Dart, a client-optimized language for building fast apps on any platform, provides a plethora of built-in types that make app development easier, more efficient, and robust. In this article, we'll unravel the rich tapestry of built-in types in Dart, shedding light on the syntax and the unique features they bring to the table.

1. Overview of Built-in Types

Dart has a special affinity for the following types:

• Numbers: int, double

• Strings: String

• Booleans: bool

• Records: (value1, value2)

• Lists: List (also termed as arrays)

• Sets: Set

• Maps: Map

• Runes: Runes

• Symbols: Symbol

• Null: Null

Literals make it possible to create objects directly. For instance, 'Hello, World!' is a string literal, while true represents a boolean literal. But, Dart goes beyond just literals. Almost every variable in Dart is an object instance, and many of these types come with built-in constructors. For example, the Map() constructor lets you craft a map.

Special roles in the Dart ecosystem are also played by:

• Object: The universal superclass, barring Null.

• Enum: Paves the way for enumerations.

• Future & Stream: The cornerstones of asynchrony.

• Iterable: Essential for for-in loops and generator functions.

• Never: Represents expressions that will never fully evaluate.

• dynamic: When you need to turn off static checking.

• void: The black hole type – values that get sucked in are never used.

2. Cracking the Code on Numbers

Dart categorizes numbers into:

• int: Integer values can span up to 64 bits, influenced by the platform.

• double: 64-bit floating-point numbers, compliant with the IEEE 754 standard.

Both of these are under the umbrella of num, which supports basic arithmetic operations. The dart:math library comes to your aid if you need advanced operations.

A unique feature is how Dart handles integer and double conversions. An integer is auto-converted to a double when required. Also, you can switch between string representations of numbers and their actual values seamlessly.

var one = int.parse('1'); 
String piAsString = 3.14159.toStringAsFixed(2);

3. Weaving Words with Strings

Strings in Dart hold sequences of UTF-16 code units. You can weave strings using single or double quotes, escape sequences, and even use string interpolation to insert an expression's value directly into a string.

String concatenation in Dart is intuitive and versatile:

var combined = 'String interpolation in ' + 'Dart is powerful!';

For multi-line strings, Dart provides triple quotes. Furthermore, "raw" strings, prefixed with r, consider every character as a literal, turning escape sequences inert.

4. Binary Logic with Booleans

In Dart, booleans are either true or false. Dart values type safety, ensuring developers can't mistakenly pass non-boolean values where boolean values are expected.

5. A Symphony of Symbols and Runes

Runes open the world of Unicode to developers. Unicode assigns unique numeric values to characters from all global writing systems. In Dart, runes let you access a string’s Unicode points directly.

If you're intrigued by emojis like 😆 or special characters like ♥, they have Unicode representations like \u{1f606} and \u2665, respectively. For intricate manipulations involving Unicode characters, Dart provides the characters package.

Symbols, on the other hand, are crucial when referring to identifiers by name, especially in the face of minification. With symbol literals, represented by # followed by the identifier, Dart provides a direct reference to an identifier, immune to name changes.

Conclusion

Dart’s built-in types not only provide robustness to the language but also ensure that developers can write concise and efficient code. From numbers to strings, and symbols to runes, Dart caters to every need, laying the foundation for fast, platform-agnostic app development.

Whether you're new to Dart or brushing up on the basics, understanding these built-in types can empower you to craft more optimized, readable, and efficient applications. Happy coding!