The Overlaps OptionThe Overlaps option for StringCases, StringPosition, and StringCount deals with how the matcher proceeds after finding a match. It has three possible settings: False, True, or All. The default is False for StringCases and StringCount, while it is True for StringPosition. With Overlaps->False, the matcher continues the match testing at the character following the last matched substring. In[60]:=  |
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With Overlaps->True, the matcher continues at the character following the first character of the last matched substring (when a single pattern is involved). In[61]:=  |
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With Overlaps->All, the matcher keeps starting at the same position until no more new matches are found. In[62]:=  |
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If multiple patterns are given in a list, Overlaps->True will cause the matcher to start at the same position once for each of the patterns before proceeding to the next character. In[63]:=  |
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Note that with Overlaps->True, there can thus be a difference between specifying a list of patterns and using the alternatives operator (|). In[65]:=  |
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