in reply to Regex: how to consider an unknown number of tabs?

See perlvar for 'paragraph mode' (setting $/ = '' or -000): 

C:\test>type junk.dat
c114: 0245, 0456, 1545
        2555, 2444, 0344
        0444, 3434, 1434

r145: 0544, 0688, 2988
        1332, 0221, 0867
        0655, 4548, 7463

c12: 2322, 0556, 3998
        3545, 2002, 4500
        5650, 0830, 3324
        3433, 7070, 3404

C:\test>perl -000nle"/^r145/ or print" junk.dat
c114: 0245, 0456, 1545
        2555, 2444, 0344
        0444, 3434, 1434

c12: 2322, 0556, 3998
        3545, 2002, 4500
        5650, 0830, 3324
        3433, 7070, 3404

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