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What does "(say)" mean in this Java method?

Since Mapper and Reducer are separate classes, the type parameters have different scopes, and the actual type argument of KEYIN (say) in the Mapper may be different from the type of the type parameter of the same name (KEYIN) in the Reducer. For instance, in the maximum temperature example from earlier chapters, KEYIN in replaced by longWritaeble for the Mapper and by Text for the Reducer.

From Hadoop The Definitive Guide, by Tom White, page 224 (scanned version of the page at 223 and 224).

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    I think that's a typo. I think it should say KEYIN(key) or simply KEYIN. You can probably safely ignore it. – Robert Harvey Jul 25 '13 at 0:04
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    Good Effort, to scan the page and upload it. Thumbs Up for the Effort. – JNL Jul 25 '13 at 0:28
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    Interesting gray area: english.SE or programmers.SE ... not sure which one it really belongs on :) – Alok Jul 25 '13 at 1:22
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    @RobertHarvey: No. It is saying simply KEYIN. The "say" is typeset with text font, not symbol font. – Jan Hudec Jul 25 '13 at 7:05
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    @chiron: Read up on "Fair Use." en.wikipedia.org/wiki/Fair_use – Robert Harvey Jul 25 '13 at 15:48
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I read that (say) in this case as 'for example', i.e. type parameter of the others could also vary between the Mapper and the Reducer.

So, I'm parsing it to mean that KEYIN, KEYOUT, VALUEIN, VALUEOUT could each have different type arguments in the Reducer as compared to their corresponding Mapper arg types.

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3

The use of "say" in the passage is another way of writing "for example" posing a hypothetical.

An example of this usage seen on English.SE - How to punctuate an example indicated by “say” which shows "parenthetical commas":

"If you have (say) a bucket..."

In the paragraph, "For instance" follows this sentence and an editor may find it wordy to use another clause construct that starts with "for". It is easier to modify the one in the middle of a sentence to "say" rather than the one that starts a sentence.

An identical meaning of the text:

Since Mapper and Reducer are separate classes, the type parameters have different scopes, and the actual type argument of KEYIN, for example, in the Mapper may be different from the type of the type parameter of the same name (KEYIN) in the Reducer. For instance, in the maximum temperature example from earlier chapters, KEYIN in replaced by longWritaeble for the Mapper and by Text for the Reducer.

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There's no doubt that it is just the usage of the english word 'say' and I don't think it has anything to do with Java.

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    Other comments and answers would contradict your answer. Consider expanding upon your answer to explain why there's no doubt about what it should mean. – user53019 Jul 25 '13 at 16:23
  • @GlenH7 I interpret this answer as a fairly straight-forward, and consistent with the other answers, in short this is just a question about the meaning of a word that is independent of the specific programming language. Am I missing something? – David LeBauer Jul 26 '13 at 0:08

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