That word is seen at http://www.gotw.ca/gotw/084.htm. I really can't find it in the dictionary.
Next, replace(): Truth be told, the ten-count'em-ten replace() members are less interesting than they are tedious and exhausting.
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The source text is a description of a program and its design characteristics. The functions include insert(), append(), replace() and erase() and others.
The text makes light of the fact that there is so much use of replace(). An old hawker's sales patter might include such encouragement about the quantity of the deal with the phrase, "You get ten, count 'em, ten, for this ridiculously low price." In this text he is over using this tired trope starting with "six, count 'em, six" and moving through eight and finally ten. I've counted enough.
It's not so much a word as it is a transcription of dialog being used as a word, for effect. English lets you do that, anything can be used as any part of speech (you can for instance noun verbs and verb nouns) if it gets the effect you're after.
Here, nouning half a conversation is an allusion to a context in which those words would be uttered, as a reaction to apparent (or imagined) incredulity, and specifically referencing comically-desperate salesmen trying to fast-talk customers into buying a pig in a poke, into accepting an offer of shall we say dubious worth. It's a self-deprecating joke about the quality of the code he's describing.