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@ -375,7 +375,16 @@ Initial values across multiple runs of the program
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When declaring values with an initial value, this value will be set into the variable each time
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the program reaches the declaration again. This can be in loops, multiple subroutine calls,
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or even multiple invocations of the entire program. If you omit an initial value, it will
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or even multiple invocations of the entire program.
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.. sidebar::
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Zeroing not for ZP
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If a variable gets allocated in zero-page, it will *not* be set to zero for you at
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the start of the program. Instead, it will simply be whatever the last value in that zero page
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location was. Code should not depend on the uninitialized starting value of such variables.
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If you omit an initial value, it will
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be set to zero *but only for the first run of the program*. A second run will utilize the last value
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where it left off (but your code will be a bit smaller because no initialization instructions
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are generated)
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@ -387,15 +396,6 @@ If you do modify them in-place, you should take care yourself that they work as
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expected when the program is restarted.
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(This is an optimization choice to avoid having to store two copies of every string and array)
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.. caution::
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variables that get allocated in zero-page will *not* have a zero starting value when you omit
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the variable's initialization. They'll be whatever the last value in that zero page
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location was. So it's best to don't depend on the uninitialized starting value!
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.. warning::
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this behavior may change in a future version so that subsequent runs always
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use the same initial values
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Loops
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-----
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