I'm sorry - English is not my first language, nor my second or third, so I'm not necessarily familiar with all the colloquialisms. I know of the phrase "flogging a dead horse", but I'm unaware of the meaning of "beating a dead cow". Is this cockney slang for some sexual activity? It is maybe a bit telling, but my knowledge of the English language is mostly restricted to phrases that occur in polite conversation. I'm happy that you try to contribute back by helping me widen my vocabulary, but maybe you can explain in simple words what this phrase is supposed to express.
As for the parts more closely related to Perl - it might not have been an explicit lesson by either merlyn or brian d foy, but neither Perl nor the authors of Perl modules are restricted to using only words in your dictionary. This fact might have come to your attention already as Perl let you use variable names such as $Filename2Fields instead of $File_name_to_fields. If the author of a module you use documents the name of a function, it is conventional to use that documented name to access that function instead of another name you'd have chosen instead. Perl supports you to modify your code to use the cromulent function names chosen by others, as it advises you when you use a different name for a function that the module author did not name in the same way.
Of course, you are free to lament these literary disagreements and claim them as "bugs". You can of course write copy-edited Perl-code, but to expect that Perl and Perl authors adhere to your seemingly limited dictionary strikes me as a quite surprising stance, especially as there are quite a lot of Perl module authors who do not share your upbringing nor a copy of your dictionary. If you think that your vocabulary is the be-all end-all epitome of literacy, I recommend you start an initiative to convince all Perl programmers to only use words you approve of in function names and variable names. Until then though, I recommend that you start reading and understanding the error messages Perl so helpfully tries to provide you with, instead of claiming bugs in Perl. Especially reading the documentation of modules, and if in doubt, reading the source code of modules usually brings great enlightenmend as towards the vocabulary that other module authors use and offer to you to use as well.