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15.5: Expressions and Statements

  • Page ID
    15359
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    An expression is a combination of values, variables, and operators. A value all by itself is considered an expression, and so is a variable, so the following are all legal expressions (assuming that the variable x has been assigned a value):

    17
    x
    x + 17
    

    A statement is a unit of code that the Python interpreter can execute. We have seen two kinds of statement: print and assignment.

    Technically an expression is also a statement, but it is probably simpler to think of them as different things. The important difference is that an expression has a value; a statement does not.


    This page titled 15.5: Expressions and Statements is shared under a CC BY-NC-SA 3.0 license and was authored, remixed, and/or curated by Allen B. Downey (Green Tea Press) .

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