Beefy Boxes and Bandwidth Generously Provided by pair Networks
Keep It Simple, Stupid
 
PerlMonks  

Re^3: Regular expressions: interpolate the variable in the value of the number of repetitions for the group

by rjt (Deacon)
on Aug 03, 2013 at 10:29 UTC ( #1047690=note: print w/ replies, xml ) Need Help??


in reply to Re^2: Regular expressions: interpolate the variable in the value of the number of repetitions for the group
in thread Regular expressions: interpolate the variable in the value of the number of repetitions for the group

Heh... Thanks, but I want to do it the forces of the regular expression (without external code).

The really funny thing is, all of the broken examples you cite as somehow desirable in the root node execute "external code" (which I take to mean non-regex Perl code), via the experimental features (?{ ... }) and (??{ ... }):

0day's code:

$binary_data =~ /(.)(.){(?{unpack 'H*', $1})}/; # ? /(.)(?{unpack 'H*', $1})(.){$^R}/; # ??? /(.)((??{'.' x $1}))/; /(\d)((??{'.*?\n' x $1}))/;

how to assign a value aaaa\n of $3, bbbb\n -> $4 etc ?

Short answer: you can't, unless you're OK with this:

/(\d) ([^\d]+?\n)? ([^\d]+?\n)? ([^\d]+?\n)? ([^\d]+?\n)? ([^\d]+?\n)? ([^\d]+?\n)? ([^\d]+?\n)? ([^\d]+?\n)? ([^\d]+?\n)? /x; printf "%d: <%s>\n", $_, eval '$'.$_ for 2..$1+1;

But, no doubt you already thought of that. I want to help you, and to do that, I need a complete description of the actual problem you're trying to solve that you need our help with, as well as some real examples of input and expected output.


Comment on Re^3: Regular expressions: interpolate the variable in the value of the number of repetitions for the group
Select or Download Code

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://1047690]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others meditating upon the Monastery: (8)
As of 2014-09-20 02:43 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    How do you remember the number of days in each month?











    Results (151 votes), past polls