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pub get

Learn to install packages with pub get.

dart pub get

dart pub get fetches the dependencies listed in pubspec.yaml. It creates a .dart_tool/ folder and a pubspec.lock file. This is done before using packages.

pubspec.lock pins the downloaded versions; your teammates use the same versions. pubspec.yaml states the request, pubspec.lock the real version.

When you add or change a dependency you run dart pub get again.

Version pinning

pubspec.yaml writes the requested version range: ^1.0.0 asks for the newest 1.x. pubspec.lock freezes the actually downloaded version.

This way everyone on the team uses the same version. pubspec.lock is committed in app projects; usually not in libraries.

dart pub upgrade raises the lock; it takes new compatible versions.

Practice dart:math and pow

Import the math library with import 'dart:math';. In main print the result of pow(2, 10).toInt() with print.

Starter code

main.dart
// Import the dart:math library

void main() {
  // print the result of 2 to the power of 10
}

Sample solution

main.dart
import 'dart:math';

void main() {
  print(pow(2, 10).toInt());
}

Expected output

1024

Questions and answers

Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.

1 The lock file

Question 
pubspec.____
Answer 
pubspec.lock

Explanation: pubspec.lock pins the versions.

2 What does dart pub get create?

  • pubspec.yaml
  • README
  • pubspec.lock and .dart_tool Correct answer
  • main.dart

Explanation: pub get creates pubspec.lock and .dart_tool.

3 pub get parts

Term Meaning
dart pub get Fetches
pubspec.lock Pins versions
.dart_tool Tool folder
pubspec.yaml Request list

All lessons in Intermediate

1 Classes in depth

  1. Constructor types
  2. Named constructors
  3. Initializer list
  4. const constructor
  5. factory
  6. Summary - Classes

2 Inheritance

  1. extends
  2. super
  3. Override
  4. abstract
  5. interface
  6. Summary - Inheritance

3 Project: Helper library

  1. Module design
  2. String helpers
  3. Number helpers
  4. Date helpers
  5. Putting it together

4 Encapsulation

  1. private
  2. Getters and setters
  3. final and const fields
  4. late
  5. static
  6. Summary - Encapsulation

5 Mixins

  1. mixin
  2. Using mixins
  3. mixin constraints
  4. Multiple mixins
  5. mixin vs inheritance
  6. Summary - Mixins

6 Generics

  1. Generic class
  2. Generic methods
  3. Type constraints
  4. Generic collections
  5. Generics vs dynamic
  6. Summary - Generics

7 Project: Quiz app

  1. Quiz model
  2. Adding questions
  3. Running the quiz
  4. Score calculation
  5. Putting it together

8 Collections

  1. List
  2. Set
  3. Map
  4. Queue
  5. Iterable
  6. Summary - Collections

9 Collection methods

  1. map
  2. where
  3. fold and reduce
  4. forEach
  5. any and every
  6. Summary - Collection methods

10 Project: Library app

  1. Model design
  2. Library class
  3. Checking out
  4. Search and filter
  5. Putting it together

11 Async in depth

  1. Future
  2. async/await
  3. Future chaining
  4. Future.wait
  5. Completer
  6. Summary - Async

12 Streams

  1. What are streams?
  2. Listening to streams
  3. Stream transformation
  4. asyncExpand
  5. StreamController
  6. Summary - Streams

13 Type aliases

  1. typedef
  2. Type alias
  3. Record
  4. Pattern matching
  5. switch expression
  6. Summary - Type aliases

14 Metadata and annotations

  1. Metadata
  2. Custom annotations
  3. @override
  4. @deprecated
  5. Reflection
  6. Summary - Metadata

15 Testing

  1. dart test
  2. test and expect
  3. group
  4. setUp and tearDown
  5. Mock
  6. Summary - Testing

16 File I/O

  1. dart:io
  2. File.readAsString
  3. File.writeAsString
  4. exists
  5. Directory
  6. Summary - File I/O

17 Packages

  1. pub
  2. pubspec.yaml
  3. pub get
  4. import
  5. pub publish
  6. Summary - Packages

18 Advanced error handling

  1. Exception hierarchy
  2. Error vs Exception
  3. Stack trace
  4. Result pattern
  5. Async errors
  6. Summary - Advanced error handling

19 Documentation

  1. dartdoc
  2. Doc comments
  3. Markdown
  4. @param and @return
  5. Example code
  6. Summary - Documentation

20 Intermediate final

  1. Project design
  2. OOP model
  3. Collections
  4. File I/O
  5. Putting it together