Python Jumpstart by Building 10 Apps Transcripts
Chapter: App 7: Wizard Battle App
Lecture: Building the game loop
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Over here in PyCharm, let's knock out the first pass on our initial game loop. Now, it's probably not going to end this way,
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or probably refine it and add some enhancements, but let's just get started in kind of the same way we have with other apps.
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So, again, we are going to add our program.py file and we are going to have our main() method, we'll have our print_header(), as always
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and in this one we are going to have what we are going to call a game_loop(). And then in our main let's just go and say print_header()
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and then we'll just run the game_loop(). And finally, let's use our PyCharm live template to call the main()
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only if it's actually being executed rather than imported. So header is pretty standard as always so let's just do this,
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ok, standard header now let's focus in on this game_loop() we have here. So the concept of our game_loop() is we just want to go around and around
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getting input from the user until the game ends so let's just start really simple with the concept of going around and around,
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and so we'll just say while true and we are going to do some work here. First thing we are going to do is get some input from the user,
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so we'll call this cmd for command and this is pretty standard we'll say you attack, run away or look around.
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Like so, and let's give the users hints on which they can do so we'll say attack, run away or look. And then we have four basic outcomes here,
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one could be they actually said they want to attack and let's just print out some things we can kind of test a little loop here,
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then we'll rewrite the behaviors. So if they say a we'll say attack, elif if it's run away we'll just print('run away'),
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if they are going to look around we are going to print('look around'), and finally,
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if they hit something else and we don't know what it is we'll just say all right, you must want to exit the game,
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like if we just hit enter with no command that means you are gone, so we'll just say something like this, ok, exiting game. Bye.
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So, let's go ahead and run our app just to make sure everything is hanging together. Now, no run configuration, so we kow how to get that going.
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All right, so down here we can attack, we can look around, we can run away, or we can say enter and we should exit.
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Now, oops, we didn't really exit we just printed exit, right, that doesn't mean anything to Python just that we printed exit.
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So we can exit out of this infinite loop by just saying break and then we'll come down here and basically
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run the next line which is empty and we're done. So look around, enter, exit, perfect.
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So our little loop is running, it's time to build up the data structures with classes and objects it's going to be great.