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// Showdown extension that replaces words surrounded by singular underscores with <em> tags
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export const markdownUnderscoreExt = () => {
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    try {
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        if (!canUseNegativeLookbehind()) {
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            console.log('Showdown-underscore extension: Negative lookbehind not supported. Skipping.');
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            return [];
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        }
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        return [{
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            type: 'output',
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            regex: new RegExp('(<code(?:\\s+[^>]*)?>[\\s\\S]*?<\\/code>|<style(?:\\s+[^>]*)?>[\\s\\S]*?<\\/style>)|\\b(?<!_)_(?!_)(.*?)(?<!_)_(?!_)\\b', 'gi'),
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            replace: function (match, tagContent, italicContent) {
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                if (tagContent) {
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                    // If it's inside <code> or <style> tags, return unchanged
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                    return match;
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                } else if (italicContent) {
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                    // If it's an italic group, apply the replacement
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                    return '<em>' + italicContent + '</em>';
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                }
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                // If none of the conditions are met, return the original match
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                return match;
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            },
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        }];
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    } catch (e) {
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        console.error('Error in Showdown-underscore extension:', e);
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        return [];
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    }
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};
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function canUseNegativeLookbehind() {
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    try {
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        new RegExp('(?<!_)');
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        return true;
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    } catch (e) {
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        return false;
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    }
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}