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postscript [2020/02/23 10:20] christian [Get the code] |
postscript [2020/02/23 10:23] christian [PostScript programming introduction] |
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| * **system dict** " | * **system dict** " | ||
| - | New definitions are put into the topmost dictionary of the stack. This allows programs to override system definitions. The NeWS(([[https:// | + | New definitions are put into the topmost dictionary of the stack. This allows programs to override system definitions. The NeWS system from Sun used this to implement an object oriented Display PostScript with the dictionaries as classes. Another view is to see the dictionaries as namespaces. |
| The dictionaries can be named with an interesting trick: the dictionary itself is stored under a key which is interpreted as its name. The system dict for example is constructed like: | The dictionaries can be named with an interesting trick: the dictionary itself is stored under a key which is interpreted as its name. The system dict for example is constructed like: | ||