I don't understand the utility of sub buildTestFile, please can you explain ?

GrandFather has posted an SSCCE which is the best way to illustrate some situation in code. Rather than distribute countless MB of data as the input (which would have been rather impolite), the SSCCE builds them on the fly. This is what buildTestFile does.

Wht is the utility of %words! that we don't use in any other part of the code

Using the hash forces uniqueness as this is a property of hash keys.

In reply to Re^3: compare two text file line by line, how to optimise by hippo
in thread compare two text file line by line, how to optimise by thespirit

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