README.md (2556B)
1 # Hello World 2 3 The classical introductory exercise. Just say "Hello, World!". 4 5 ["Hello, World!"](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program) is 6 the traditional first program for beginning programming in a new language 7 or environment. 8 9 The objectives are simple: 10 11 - Write a function that returns the string "Hello, World!". 12 - Run the test suite and make sure that it succeeds. 13 - Submit your solution and check it at the website. 14 15 If everything goes well, you will be ready to fetch your first real exercise. 16 17 ## Exception messages 18 19 Sometimes it is necessary to raise an exception. When you do this, you should include a meaningful error message to 20 indicate what the source of the error is. This makes your code more readable and helps significantly with debugging. Not 21 every exercise will require you to raise an exception, but for those that do, the tests will only pass if you include 22 a message. 23 24 To raise a message with an exception, just write it as an argument to the exception type. For example, instead of 25 `raise Exception`, you should write: 26 27 ```python 28 raise Exception("Meaningful message indicating the source of the error") 29 ``` 30 31 ## Running the tests 32 33 To run the tests, run the appropriate command below ([why they are different](https://github.com/pytest-dev/pytest/issues/1629#issue-161422224)): 34 35 - Python 2.7: `py.test hello_world_test.py` 36 - Python 3.4+: `pytest hello_world_test.py` 37 38 Alternatively, you can tell Python to run the pytest module (allowing the same command to be used regardless of Python version): 39 `python -m pytest hello_world_test.py` 40 41 ### Common `pytest` options 42 43 - `-v` : enable verbose output 44 - `-x` : stop running tests on first failure 45 - `--ff` : run failures from previous test before running other test cases 46 47 For other options, see `python -m pytest -h` 48 49 ## Submitting Exercises 50 51 Note that, when trying to submit an exercise, make sure the solution is in the `$EXERCISM_WORKSPACE/python/hello-world` directory. 52 53 You can find your Exercism workspace by running `exercism debug` and looking for the line that starts with `Workspace`. 54 55 For more detailed information about running tests, code style and linting, 56 please see [Running the Tests](http://exercism.io/tracks/python/tests). 57 58 ## Source 59 60 This is an exercise to introduce users to using Exercism [http://en.wikipedia.org/wiki/%22Hello,_world!%22_program](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program) 61 62 ## Submitting Incomplete Solutions 63 64 It's possible to submit an incomplete solution so you can see how others have completed the exercise.