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4. AN IMPLEMENTATION 4.6. Generation of Original Syntax
!"#$%&'
)*++
(
!"#$%&'
,
!"#$%&'
-
)*++
Figure 4.3: List of TGRNodes
!"#$%&'
!"#$%&'
the grammar where the current was based on and a TGRNode list next containing the gram-
mars based on the current. An example is represented in Figure 4.3.
To allow the user to traverse all the built grammars, the prev and next methods resort to
each grammar serial number to iterate the grammars backwards/forwards. Each method may
also return null if no grammar was built before/after the current one, respectively. The get
method receives an integer representing the desired grammar serial number and returns the
respective Grammar.
The discard method deletes a grammar from the database, and every grammar based on
that one. The discardAll empties the list of tentative grammars. To save the state of the
database, the gramar list is stored to disk.
4.6 Generation of Original Syntax
The generation of original syntax consists on printing a file on generic syntax back to its original
syntax by means of a Printer component. When a file is transposed from its original syntax,
say INI, to the generic syntax (XML), the language-specific details, like the ‘[’ and ‘]’ header
delimiters, are discarded to allow for application-independent configuration. Furthermore, the
format of each pattern is also lost. Only the relevant information for the configuration process,
such as parameter keys and values, is kept.
When the printer tries to print the file in generic syntax back to its original form, it will
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/
.
)*++
)*++