In reply to RAGHURAJA:
With UVM-1.2 the sequence library construct is part of the UVM standard. It has 2 aspects. Firstly it as a structure to organize sequences belonging together. secondly it simplifies the handling of sequences belonging together. You can execute a sequence libaray like a sequence.
The definition looks like this:
class my_seq_lib extends uvm_sequence_library #(my_item);
uvm_object_utils(my_seq_lib) uvm_sequence_library_utils(my_seq_lib)
function new(string name=“”);
super.new(name);
init_sequence_library();
endfunction
…
endclass
For adding, getting and removing sequences from the library see the UVM Refernece Manual 1.2.