LineReader
![Software License][ico-license]
[
][link-ghactions], (*1)
LineReader is a library to read large files line by line in a memory efficient (constant) way., (*2)
Install
Via Composer, (*3)
$ composer require bcremer/line-reader
Usage
Given we have a textfile (some/file.txt) with lines like:, (*4)
Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Line 7
Line 8
Line 9
Line 10
Also let's assume the namespace is imported to keep the examples dense:, (*5)
use Bcremer\LineReader\LineReader;
Read forwards
foreach (LineReader::readLines('some/file.txt') as $line) {
echo $line . "\n"
}
The output will be:, (*6)
Line 1
Line 2
Line 3
Line 4
Line 5
...
To set an offset or a limit use the \LimitIterator:, (*7)
$lineGenerator = LineReader::readLines('some/file.txt');
$lineGenerator = new \LimitIterator($lineGenerator, 2, 5);
foreach ($lineGenerator as $line) {
echo $line . "\n"
}
Will output line 3 to 7, (*8)
Line 3
Line 4
Line 5
Line 6
Line 7
Read backwards
foreach (LineReader::readLinesBackwards('some/file.txt') as $line) {
echo $line;
}
Line 10
Line 9
Line 8
Line 7
Line 6
...
Example: Read the last 5 lines in forward order:, (*9)
$lineGenerator = LineReader::readLinesBackwards('some/file.txt');
$lineGenerator = new \LimitIterator($lineGenerator, 0, 5);
$lines = array_reverse(iterator_to_array($lineGenerator));
foreach ($line as $line) {
echo $line;
}
Line 6
Line 7
Line 8
Line 9
Line 10
Testing
$ composer test
$ TEST_MAX_LINES=200000 composer test
License
The MIT License (MIT). Please see License File for more information., (*10)
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