Diff Class Reference

Inheritance diagram for Diff:

Collaboration diagram for Diff:

Public Member Functions
	__construct ($from_lines, $to_lines)
	Constructor. More...
	reverse ()
	Compute reversed Diff. More...
	isEmpty ()
	Check for empty diff. More...
	lcs ()
	Compute the length of the Longest Common Subsequence (LCS). More...
	orig ()
	Get the original set of lines. More...
	closing ()
	Get the closing set of lines. More...
	_check ($from_lines, $to_lines)
	Check a Diff for validity. More...

Data Fields
	$edits

Detailed Description

Definition at line 611 of file class.WordLevelDiff.php.

Constructor & Destructor Documentation

__construct()

Diff::__construct	(		$from_lines,
			$to_lines
	)

Constructor.

Computes diff between sequences of strings.

Parameters

$from_lines	array An array of strings. (Typically these are lines from a file.)
$to_lines	array An array of strings.

Definition at line 623 of file class.WordLevelDiff.php.

    {
        $eng = new _DiffEngine();
        $this->edits = $eng->diff($from_lines, $to_lines);
        //$this->_check($from_lines, $to_lines);
    }

Member Function Documentation

_check()

Diff::_check	(		$from_lines,
			$to_lines
	)

Check a Diff for validity.

This is here only for debugging purposes.

Definition at line 728 of file class.WordLevelDiff.php.

References _DiffOp\reverse().

    {
        $fname = 'Diff::_check';
        //wfProfileIn( $fname );
        if (serialize($from_lines) != serialize($this->orig())) {
            trigger_error("Reconstructed original doesn't match", E_USER_ERROR);
        }
        if (serialize($to_lines) != serialize($this->closing())) {
            trigger_error("Reconstructed closing doesn't match", E_USER_ERROR);
        }

        $rev = $this->reverse();
        if (serialize($to_lines) != serialize($rev->orig())) {
            trigger_error("Reversed original doesn't match", E_USER_ERROR);
        }
        if (serialize($from_lines) != serialize($rev->closing())) {
            trigger_error("Reversed closing doesn't match", E_USER_ERROR);
        }


        $prevtype = 'none';
        foreach ($this->edits as $edit) {
            if ($prevtype == $edit->type) {
                trigger_error("Edit sequence is non-optimal", E_USER_ERROR);
            }
            $prevtype = $edit->type;
        }

        $lcs = $this->lcs();
        trigger_error('Diff okay: LCS = ' . $lcs, E_USER_NOTICE);
        //wfProfileOut( $fname );
    }

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closing()

Diff::closing

(

)

Get the closing set of lines.

This reconstructs the $to_lines parameter passed to the constructor.

Returns

array The sequence of strings.

Definition at line 711 of file class.WordLevelDiff.php.

    {
        $lines = array();

        foreach ($this->edits as $edit) {
            if ($edit->closing) {
                array_splice($lines, sizeof($lines), 0, $edit->closing);
            }
        }
        return $lines;
    }

isEmpty()

Diff::isEmpty

(

)

Check for empty diff.

Returns

bool True iff two sequences were identical.

Definition at line 655 of file class.WordLevelDiff.php.

    {
        foreach ($this->edits as $edit) {
            if ($edit->type != 'copy') {
                return false;
            }
        }
        return true;
    }

lcs()

Diff::lcs

(

)

Compute the length of the Longest Common Subsequence (LCS).

This is mostly for diagnostic purposed.

Returns

int The length of the LCS.

Definition at line 672 of file class.WordLevelDiff.php.

    {
        $lcs = 0;
        foreach ($this->edits as $edit) {
            if ($edit->type == 'copy') {
                $lcs += sizeof($edit->orig);
            }
        }
        return $lcs;
    }

orig()

Diff::orig

(

)

Get the original set of lines.

This reconstructs the $from_lines parameter passed to the constructor.

Returns

array The original sequence of strings.

Definition at line 691 of file class.WordLevelDiff.php.

    {
        $lines = array();

        foreach ($this->edits as $edit) {
            if ($edit->orig) {
                array_splice($lines, sizeof($lines), 0, $edit->orig);
            }
        }
        return $lines;
    }

reverse()

Diff::reverse

(

)

Compute reversed Diff.

SYNOPSIS:

$diff = new Diff($lines1, $lines2); $rev = $diff->reverse();

Returns

object A Diff object representing the inverse of the original diff.

Definition at line 640 of file class.WordLevelDiff.php.

    {
        $rev = $this;
        $rev->edits = array();
        foreach ($this->edits as $edit) {
            $rev->edits[] = $edit->reverse();
        }
        return $rev;
    }

Field Documentation

$edits

Diff::$edits

Definition at line 613 of file class.WordLevelDiff.php.

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The documentation for this class was generated from the following file:

• Services/COPage/mediawikidiff/class.WordLevelDiff.php