Python for Absolute Beginners Transcripts
Chapter: Organizing and reusing code with functions
Lecture: Concept: A simple functions
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Let's review this concept of functions
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and functions that take inputs
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and have return values.
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We're going to encapsulate the idea of playing around.
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This was basically the inside
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of that loop that we built in the previous example.
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And in order to do that
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we're going to have to pass in
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the names of the two players.
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Here we just embed, or have, the roles right here.
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This is kind of isolated so it's not exactly
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the same as before
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but we have these three roles
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and then we're going to print out what they were
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just so that folks can see what roles they can play.
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And then there's some logic to find the winner
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that's probably getting to role from the one
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or both of the players.
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And then, comparing whether or not
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you know, if they rolled rock
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did the other paper roll paper?
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Whatever it was, once we figure that out
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we set some variable we're not talking about explicitly.
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player_1 wins, or player_2 wins.
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And if player_1 wins, we're going to return player_1's
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the string or the name of the player
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otherwise player_2.
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And if player_1 doesn't win
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and two doesn't win
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well, must be a tie.
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So we're going to return none like we did before.
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This is a bit of a simplification
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but the things I want you to take away here
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are we start all functions with the keyword def.
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D-E-F.
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And then we have a space.
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And then we give it a name.
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And this name can be any valid, variable, name, in Python.
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For example, it can't start with a number
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but the rules are pretty open, right?
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After that.
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And then it's going to take zero or more pieces of data.
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In this case it takes two
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the name of player_1, and the name of player_2.
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And then it's going to return some data.
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Now when we talk about the function up at the top line
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we don't indicate returning any data.
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Some languages do, they actually say
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This function takes these two players and it returns
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you know, the name string, or something like that.
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In Python we don't do that.
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We just either return it or we don't.
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So down in the bottom
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we're going to either return a string
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or we're going to return none.
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So we can check whoever calls this.
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Did somebody win?
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Here they are, otherwise, nobody won
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that must be a tie.
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This is how we create simple functions.
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And they're incredibly useful as you saw
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throughout that example.
