bool update (CodeDocument& codeDoc, int lineNum,
                 CodeDocument::Iterator& source,
                 CodeTokeniser* tokeniser, const int tabSpaces,
                 const CodeDocument::Position& selStart,
                 const CodeDocument::Position& selEnd)
    {
        Array <SyntaxToken> newTokens;
        newTokens.ensureStorageAllocated (8);

        if (tokeniser == nullptr)
        {
            const String line (codeDoc.getLine (lineNum));
            addToken (newTokens, line, line.length(), -1);
        }
        else if (lineNum < codeDoc.getNumLines())
        {
            const CodeDocument::Position pos (codeDoc, lineNum, 0);
            createTokens (pos.getPosition(), pos.getLineText(),
                          source, *tokeniser, newTokens);
        }

        replaceTabsWithSpaces (newTokens, tabSpaces);

        int newHighlightStart = 0;
        int newHighlightEnd = 0;

        if (selStart.getLineNumber() <= lineNum && selEnd.getLineNumber() >= lineNum)
        {
            const String line (codeDoc.getLine (lineNum));

            CodeDocument::Position lineStart (codeDoc, lineNum, 0), lineEnd (codeDoc, lineNum + 1, 0);
            newHighlightStart = indexToColumn (jmax (0, selStart.getPosition() - lineStart.getPosition()),
                                               line, tabSpaces);
            newHighlightEnd = indexToColumn (jmin (lineEnd.getPosition() - lineStart.getPosition(), selEnd.getPosition() - lineStart.getPosition()),
                                             line, tabSpaces);
        }

        if (newHighlightStart != highlightColumnStart || newHighlightEnd != highlightColumnEnd)
        {
            highlightColumnStart = newHighlightStart;
            highlightColumnEnd = newHighlightEnd;
        }
        else if (tokens == newTokens)
        {
            return false;
        }

        tokens.swapWith (newTokens);
        return true;
    }
    bool update (CodeDocument& document, int lineNum,
                 CodeDocument::Iterator& source,
                 CodeTokeniser* analyser, const int spacesPerTab,
                 const CodeDocument::Position& selectionStart,
                 const CodeDocument::Position& selectionEnd)
    {
        OwnedArray <SyntaxToken> newTokens;

        if (analyser == 0)
        {
            newTokens.add (new SyntaxToken (document.getLine (lineNum), -1));
        }
        else if (lineNum < document.getNumLines())
        {
            const CodeDocument::Position pos (&document, lineNum, 0);
            createTokens (pos.getPosition(), pos.getLineText(),
                          source, analyser, newTokens);
        }

        replaceTabsWithSpaces (newTokens, spacesPerTab);

        int newHighlightStart = 0;
        int newHighlightEnd = 0;

        if (selectionStart.getLineNumber() <= lineNum && selectionEnd.getLineNumber() >= lineNum)
        {
            const String line (document.getLine (lineNum));

            CodeDocument::Position lineStart (&document, lineNum, 0), lineEnd (&document, lineNum + 1, 0);
            newHighlightStart = indexToColumn (jmax (0, selectionStart.getPosition() - lineStart.getPosition()),
                                               line, spacesPerTab);
            newHighlightEnd = indexToColumn (jmin (lineEnd.getPosition() - lineStart.getPosition(), selectionEnd.getPosition() - lineStart.getPosition()),
                                             line, spacesPerTab);
        }

        if (newHighlightStart != highlightColumnStart || newHighlightEnd != highlightColumnEnd)
        {
            highlightColumnStart = newHighlightStart;
            highlightColumnEnd = newHighlightEnd;
        }
        else
        {
            if (tokens.size() == newTokens.size())
            {
                bool allTheSame = true;

                for (int i = newTokens.size(); --i >= 0;)
                {
                    if (*tokens.getUnchecked(i) != *newTokens.getUnchecked(i))
                    {
                        allTheSame = false;
                        break;
                    }
                }

                if (allTheSame)
                    return false;
            }
        }

        tokens.swapWithArray (newTokens);
        return true;
    }