Icon+Unicon/Intro: Difference between revisions
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Files and windows (mutable) allow Icon/Unicon to interface with the operating system. Operations on files and windows have side effects and they are considered mutable. Sockets and pipes are also implemented as "files". |
Files and windows (mutable) allow Icon/Unicon to interface with the operating system. Operations on files and windows have side effects and they are considered mutable. Sockets and pipes are also implemented as "files". |
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== Declarations, it's all about Scope == |
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Icon/Unicon doesn't need to declare the data types of variables because all data is safe typed and self defining. That doesn't mean variables aren't declared. By default all variables are local to their procedures. Declarations are therefore all about the scope of reference rather than type. Specifically, |
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* local - variables local to a procedure |
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* global - variables with global presence |
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* static - procedure variables that persist across calls |
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=== Intuitive Generalizations === |
=== Intuitive Generalizations === |
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