function executeConcreteSyntaxPattern()

in playground/tree-sitter/concrete-syntax.js [257:304]
33 lines of code
10 McCabe index (conditional complexity)

function executeConcreteSyntaxPattern(pattern) {
    const statusText = document.getElementById('concrete-syntax-status');
    
    statusText.textContent = 'Searching...';

    if (!window.ConcreteSyntax) {
        statusText.textContent = 'WASM not ready';
        return;
    }

    try {
        // Always get fresh source code
        let sourceCode = getFreshSourceCode();
        
        if (!sourceCode || !sourceCode.trim()) {
            statusText.textContent = 'No code';
            clearHighlights();
            return;
        }

        // Always parse fresh tree
        const languageSelect = document.getElementById('language-select');
        const currentLanguage = languageSelect ? languageSelect.value : 'python';
        
        parseFreshTree(sourceCode, currentLanguage).then(tree => {
            if (!tree || !tree.rootNode) {
                statusText.textContent = 'Parse failed';
                return;
            }

            // Execute concrete syntax matching
            const matches = executeConcreteSyntaxQuery(pattern, tree.rootNode, sourceCode);
            
            // Highlight matches in editor
            highlightMatchesInEditor(matches);
            
            statusText.textContent = matches.length > 0 ? `${matches.length} match${matches.length !== 1 ? 'es' : ''}` : 'No matches';
            
        }).catch(err => {
            console.error('Parse error:', err);
            statusText.textContent = 'Parse error';
        });
        
    } catch (error) {
        console.error('Error executing concrete syntax pattern:', error);
        statusText.textContent = 'Error';
    }
}