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regex token iterator Example

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A std::regex_token_iterator provides a tremendous tool for extracting elements of a Comma Separated Value file. Aside from the advantages of iteration, this iterator is also able to capture escaped commas where other methods struggle: 

const auto input = "please split,this,csv, ,line,\\,\n"s;
const regex re{ "((?:[^\\\\,]|\\\\.)+)(?:,|$)" };
const vector<string> m_vecFields{ sregex_token_iterator(cbegin(input), cend(input), re, 1), sregex_token_iterator() };

cout << input << endl;

copy(cbegin(m_vecFields), cend(m_vecFields), ostream_iterator<string>(cout, "\n"));

Live Example

A notable gotcha with regex iterators is, that the regex argument must be an L-value. An R-value will not work.

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Regular expressions:
* Regular expressions
* Basic regex match and regex search Examples
* regex iterator Example
* Anchors
* regex replace Example
* regex token iterator Example
* Splitting a string
* Quantifiers
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