ExplodeIterator.php

Go to the documentation of this file.

<?php
class ExplodeIterator implements Iterator {
    // The subject string
    private $subject, $subjectLength;
 
    // The delimiter
    private $delim, $delimLength;
 
    // The position of the start of the line
    private $curPos;
 
    // The position after the end of the next delimiter
    private $endPos;
 
    private $current;
 
    public function __construct( $delim, $subject ) {
        $this->subject = $subject;
        $this->delim = $delim;
 
        // Micro-optimisation (theoretical)
        $this->subjectLength = strlen( $subject );
        $this->delimLength = strlen( $delim );
 
        $this->rewind();
    }
 
    public function rewind() {
        $this->curPos = 0;
        $this->endPos = strpos( $this->subject, $this->delim );
        $this->refreshCurrent();
    }
 
    public function refreshCurrent() {
        if ( $this->curPos === false ) {
            $this->current = false;
        } elseif ( $this->curPos >= $this->subjectLength ) {
            $this->current = '';
        } elseif ( $this->endPos === false ) {
            $this->current = substr( $this->subject, $this->curPos );
        } else {
            $this->current = substr( $this->subject, $this->curPos, $this->endPos - $this->curPos );
        }
    }
 
    public function current() {
        return $this->current;
    }
 
    public function key() {
        return $this->curPos;
    }
 
    public function next() {
        if ( $this->endPos === false ) {
            $this->curPos = false;
        } else {
            $this->curPos = $this->endPos + $this->delimLength;
            if ( $this->curPos >= $this->subjectLength ) {
                $this->endPos = false;
            } else {
                $this->endPos = strpos( $this->subject, $this->delim, $this->curPos );
            }
        }
        $this->refreshCurrent();
 
        return $this->current;
    }
 
    public function valid() {
        return $this->curPos !== false;
    }
}