Student Z raises his hand in class. He says “Ok, so I guess I see a reason to do something with code other than run it. But I still think there's too much academic wankery in this field. Look at all these discussions of meaning and semantics. Who cares? Your average hacker doesn't bother with semantics, he just wants to get the job done.”
Well, obviously I'm setting up Student Z as a straw man, but how important are the semantics of a language? Are they simply a curiosity for ‘language lawyers’ and mathematicians to worry about, or are they a tool that is used daily by programmers?