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POWhy does foo = function() run the function in Python?
 

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  1. POWhy does foo = function() run the function in Python?
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    <p>I'm up to Exercise 41 in Learn Python the Hard Way, and I'm having a really hard time wrapping my brain around the fact that the entire thing hinges on a function running just because it's been assigned as a value to a variable. I wrote up a little script to confirm that this is how it works, and it does: </p> <pre><code>def pants(): print "Put on some pants!" def shorts(): print "And don't forget your underwear!" zap = pants() thing = shorts() </code></pre> <p>With the results being: </p> <pre><code>Put on some pants! And don't forget your underwear! </code></pre> <p>So obviously this happens, but I can't understand why the language works that way -- what the logic is behind the language that makes this a valuable way of operating. I think it'd be helpful for me moving forward to understand <em>why</em> this is, rather than just "that's the way it works." </p> <p>For clarity: I'm asking (I guess) why the function is running, when all I'm doing is assigning it as a value for something. The print statements are just there so I can see that the function is indeed running. </p> <p>It's the fact that I'm not ever actually running </p> <p>pants() shorts() </p> <p>that is confusing me.</p> <p>To create a tortured analogy, if me-baking-cookies-at-home were "cookies()", and I were to make cookies on Saturdays, I might eventually believe that </p> <p>Saturday = cookies()</p> <p>but just thinking "hey, Saturday is cookie day" is not the same as <em>actually baking cookies</em>... so why does just saying</p> <p>Saturday = cookies() </p> <p>actually bake the cookies, rather than just setting up Saturday with the variable "cookies()" for some later use? </p>
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    1. COYou're probably confusing `print` with `return`.
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    2. COI think Juhana might be right. Are you expecting `zap` to have a value of "Put on some pants!"? If so then change the `print` to a `return` and then `print zap` after it's been assigned.
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    3. COYes, clearly your expectations are misaligned with the language. What were you expecting?
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      1. USDavid Heffernan
 

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