in reply to How can I parse grouped data?
First define the grammar that your input obeys in a format that can be read into a parser. For example, if you choose yapp, Parse::Yapp will also tell you how to define the grammar file it needs to parse your input and how to run the relevant lexer and parser. And when you know that, the code generation should be a relatively trivial matter.
Update: The lexer, albeit simple enough for your example input, also has to be written yourself, but the linked documentation explains that thoroughly. 'Tokens' refer to the named categories of substrings you will return as grammatical elements for the parser - these might be 'TK_DIGITS' or 'TK_ID' etc. and 'values' refer to the actual value found under that category for each execution of your lexer - each such execution therefore returning a single substring and the category under which it falls.
The documentation doesn't mention that one also normally writes a throw routine to consume comments and whitespace.
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