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Dear Monks, I beg your wisdom...

I am trying to parse a string for which I need to consume dynamically determined number of characters. Can P:RD be persuaded to do that?

Here is a simple example string:
s:5:"abcde"; -- the '5' is the number of characters in the string

Here's the hard part:
s:18:"s:10:"abcdefghij";"; -- the string can store other strings, so I can't just search for ";

I know that subrules can have repetition counts, but I can't get something like
String: 's: ' Count '"' Cdata($item{Count}) '";' to work

Here's the simplified grammar. Is there a way I can consume the number of characters specified by $item{Count}?

my $grammar = q{ CompText: Command(s) Command: String | Integer Array: 'a:' <commit> Count ':{' Command(s) '}' { $return = "a:$item{Count}:{" . join( '', @{$item[-2]}) . "}" } String: 's:' Count ':"' Array '";' { $return = "s:$item{Count}:\"" . join( '', @{$item{Array}}) . + "\";" } | 's:' Count ':"' Cdata_String '";' { $return = "s:$item{Count}:\"" . join( '', @{$item[-2]}) . "\ +";" } Cdata_String: Cdata(s?) Count: /\d+/ Cdata: /./ };

Thank you,
--Michael


In reply to Parse::RecDescent - specifying dynamic subrule repetition by leahymr

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