substr($obj_strptime,index($strptime,"sub")+6,0) = <<'ESQ';
shift; # package
....
....
ESQ
What is this ESQ and what is it doing here. Please help me understand these statements;
substr($obj_strptime,index($strptime,"sub")+6,0) = <<'ESQ';
shift; # package
....
....
ESQ
What is this ESQ and what is it doing here. Please help me understand these statements;
It marks the end of a here-doc section.
EOF is more traditional than ESQ though.
Also note that the here-doc is assigned to the indicated position (index($strptime,"sub")+6) in $obj_strptime.