60 lines
1.5 KiB
Plaintext
60 lines
1.5 KiB
Plaintext
Global variables can seem like a handy way to pass state information around in a program, but the use of global variables only works well in very small programs. As the code base grows, you'll need to understand every subprocedure's impact on the global state in order to understand how the program works. This is a task that quickly becomes impossible.
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To control the situation, only the main procedure should be allowed access to global variables; it can then pass that state information to subprocedures as parameters.
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== Noncompliant Code Example
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----
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D FirstName S 20A
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D LastName S 20A
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/free
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FirstName = 'John';
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LastName = 'Smith';
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DSPLY FullName();
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/end-free
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P FullName B
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D FullName PI 41A
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/free
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return FirstName + ' ' + LastName;
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/end-Free
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P E
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----
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== Compliant Solution
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----
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/free
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DSPLY FullName('John':'Smith');
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/end-free
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P FullName B
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D FullName PI 41A
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D FirstName 20A Const
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D LastName 20A Const
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/free
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return FirstName + ' ' + LastName;
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/end-Free
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P E
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----
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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include::message.adoc[]
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'''
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== Comments And Links
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(visible only on this page)
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include::comments-and-links.adoc[]
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endif::env-github,rspecator-view[]
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