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Re: recursive /eg fails

by derby (Abbot)
on Mar 27, 2002 at 13:03 UTC ( #154651=note: print w/ replies, xml ) Need Help??

in reply to recursive /eg fails


You have no base clase case for your recursion. When you get down to the bottom call, you try to execute "func xxx returns y". Try this (tip to stephen for cleaning it up):

#!/usr/bin/perl -wd use strict; print doFunc( "MAIN", "B(1)+C(2)" ); sub doFunc{ my ($theFunc, $rem) = @_; my $re = &get_re($rem); if( $rem ne $re ) { $rem =~ s/(\w+)\(($re)\)/doFunc($1,$2)/eg; } return "func $theFunc rets $rem"; } ## ## When we're called with the initial ## state, return "1|2". Otherwise, return ## our input, quotemeta'd. ## sub get_re { my ($in) = @_; if ($in eq "B(1)+C(2)") { return '1|2'; } else { return quotemeta($in); } }


update: There's a base case and a base class (no relation) but base clase?

update: Just spent a few minutes with your original. Here's it is with the base case added:

print doFunc( "MAIN", "B(1)+C(2)" ); sub doFunc{ my $theFunc = shift; local $_ = shift; my $re; $re = ${{ "B(1)+C(2)" => '1|2', }}{$_}||quotemeta; print "$theFunc: '$_'=~/$re/\n"; print join"\n",/(\w+)\(($re)\)/g,"\n"; if( $_ ne $re ) { $_ =~ s/(\w+)\(($re)\)/&doFunc($1,$2)/eg; # /ego works /eg fails } return "func $theFunc returns <$_>"; }

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