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@suragch
Last active September 2, 2021 03:38
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How to create your own iterable
void main() {
const myString = 'This is a long string that I want to iterate over.';
final myIterable = TextRuns(myString);
for (var textRun in myIterable) {
print(textRun);
}
}
class TextRuns extends Iterable<String> {
TextRuns(this.text);
final String text;
@override
Iterator<String> get iterator => TextRunIterator(text);
}
class TextRunIterator implements Iterator<String> {
TextRunIterator(this.text);
final String text;
String? _currentTextRun;
int _startIndex = 0;
int _endIndex = 0;
final breakChar = RegExp(' ');
@override
String get current => _currentTextRun as String;
@override
bool moveNext() {
_startIndex = _endIndex;
if (_startIndex == text.length) {
_currentTextRun = null;
return false;
}
final next = text.indexOf(breakChar, _startIndex);
_endIndex = (next != -1) ? next + 1 : text.length;
_currentTextRun = text.substring(_startIndex, _endIndex);
return true;
}
}
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