Improvements for the dict commandThomas PerschakTrevor Davel$Revision: 1.3 $
The dict command is limited by allowing manipulation of only the first level of key elements. Not only should the dict get accept a nested key list, but also the other commands like dict replace.
The following line:
ZGljdCBnZXQgey1yYW5nZSB7LXZhbHVlcyB7YSBiIGN9IC1iYXNlIE19IC1uYW1lIG15bmFtZX0gXA==ICAgICAgICAtcmFuZ2UgLWJhc2U=
Results in:
TQ==
But how to change the base? I suggest the following dict syntax extension:
ZGljdCByZXBsYWNlIHstcmFuZ2Ugey12YWx1ZXMge2EgYiBjfSAtYmFzZSBNfSAtbmFtZSBteW5hbWV9IFw=ICAgICAgICB7LXJhbmdlIC1iYXNlfSBr
Results in:
LXJhbmdlIHstdmFsdWVzIHthIGIgY30gLWJhc2Uga30gLW5hbWUgbXluYW1l
Allowing a nested key list would not break any previous code, but substantially improve the dict command.
The dict command is the basis for handling database like structures. By allowing nested keys this would give more freedom in organizing these structures like the example above.
Twylite 2010/08/17: The specification states that "Allowing a nested key list would not break any previous code". This is not correct, for example:
ZGljdCByZXBsYWNlIHsiSmFuZSBTbWl0aCIgIjExIEZvbyBSb2FkIiAiSm9obiBEb2UiICJBZGRyZXNzIHVua25vd24ifSB7SmFuZSBTbWl0aH0gbmV3X2FkZHJlc3M=LT4ge0phbmUgU21pdGh9IG5ld19hZGRyZXNzIHtKb2huIERvZX0ge0FkZHJlc3MgdW5rbm93bn0=
Existing code that uses dict replace in conjunction with keys that are valid lists of 2 or more elements would break.
Also, drawing from experience, the nested key approach is a source of subtle bugs. It is natural to write code such as:
ZGljdCByZXBsYWNlICRkaWN0ICRrZXkgJHZhbHVl
but that contains a bug that is often missed during testing. The correct approach would be:
ZGljdCByZXBsYWNlICRkaWN0IFtsaXN0ICRrZXldICR2YWx1ZQ==
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