Once you get this vexed question nailed down, I think you should investigate why the substr built-in is named "substr" and not "substring", "subStr", "subString", "sub_str", "sub_string" or any of a large number of other possibilities. You may answer "Well, they had to call it something," but is just saying "The documentation says it, I believe it, that settles it!" ever really satisfactory? Question authority! (Please see perlfunc for additional raw material. Personally, I've been wondering a lot lately about grep.)
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