Hi. I have a file, which looks similar to what I have provided below. I want to extract out CONSECUTIVE lines, which do not have NIL after the '=' sign. 

 
1yxq_SWI_B_600   =   c.55.1.1-
      
      
      
1grh_ADW_A_479   =   NIL
      
      
      
      
1fm9_570_D_200   =   a.123.1.1-
      
1ec1_BEE_A_501   =   b.50.1.1-
      
1fm9_570_D_200   =   a.123.1.1-
2zmh_NYA_A___1   =   a.123.1.1-
      
1gvh_HQQ_A1398   =   a.1.1.2-c.25.1.5-
1v9y_HDQ_A1140   =   d.110.3.2-
      
1mqt_SPL_A_284   =   NIL

[download]
Thus, I would want the output to look like this: 
          
1fm9_570_D_200   =   a.123.1.1-
2zmh_NYA_A___1   =   a.123.1.1-
      
1gvh_HQQ_A1398   =   a.1.1.2-c.25.1.5-
1v9y_HDQ_A1140   =   d.110.3.2-

[download]
Please help. Thanks.

In reply to restricting matching only to consecutive lines by anasuya

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