splitAndTrim method

List<String>? splitAndTrim(String pattern, { bool removeEmpty = true, bool respectQuotes = false, })

Splits a string into a List of trimmed Strings, potentially avoiding splitting in the middle of a quoted text. if respectQuotes is true - then the string is not split between quotes. however, this functionality is (currently?) limited:

• escaping is not supported

• both ' and " are supported, but even if one is enclosed by the other - it still "counts". for example, the string: "hello ' world" will count as having a beginning ' quote. in the following examples, we use the pattern " ": hello world --> hello world

  "hello world" --> "hello world"

  "hello world" "nihao shijie" --> "hello world" "nihao shijie"

  'hello world' "nihao shijie" --> 'hello world' "nihao shijie"

  "hello 'world nihao' shijie" --> "hello 'world nihao' shijie"

  "hello 'world" nihao' shijie --> "hello 'world" nihao' shijie

  "hello 'world nihao' shijie --> "hello 'world nihao' shijie

  "hello'world" nihao'shijie --> "hello'world" nihao'shijie

  "hello'world" nihao' shijie --> "hello'world" nihao' shijie

  "hello'world" nihao' shijie' --> "hello'world" nihao' shijie'

  "hello'world" ni'hao"shi jie" --> "hello'world" ni'hao"shi jie"

Implementation

List<String>? splitAndTrim(String pattern, { bool removeEmpty = true, bool respectQuotes = false }) {
	String s = this.trim();
	if (s.isEmpty) {
		return null;
	}

	List<String> arrParts = s.split(pattern);
	List<String> arrFinal = arrParts;
	if (respectQuotes) {
		arrFinal = [ ];

		int i = 0;
		while (i < arrParts.length) {
			String part = arrParts[i];
			String? ch = part._getQuoteIfOdd();
			if (ch != null) {
				// there is an unclosed quote. find where it's closed
				int nextIdx = -1;
				if (i < arrParts.length - 1) {
					nextIdx = arrParts.indexWhere((x) => x._hasOddQuotesOf(ch), i + 1);
				}

				if (nextIdx == -1) {
					// no closing quote. so ignore the single quote
				}
				else {
					// concatenate all the remaining parts until the part we found
					arrFinal.add(arrParts.sublist(i, nextIdx + 1).join(pattern));
					i = nextIdx + 1;
					continue;
				}
			}

			// no odd quote; add the part as-is
			arrFinal.add(part);
			i++;
		}
	}

	List<String> arr = arrFinal.map((x) => x.trim()).toList();
	arr.removeWhere((x) => x.isEmpty);
	return arr;
}