regex_helper

Instructions

Implementation Reference

• src/tools/code-assistance.ts:866-928 (handler)

  Implementation of explainRegex tool handler in CodeAssistanceTools class.

    async explainRegex(
      pattern: string,
      options?: {
        flags?: string;
        generateExamples?: boolean;
      }
    ): Promise<ExplainRegexResult> {
      const flags = options?.flags ?? '';
      const includeExamples = options?.generateExamples ?? true;
  
      const prompt = `You are a regex expert. Explain this regular expression in plain English.
  
  Pattern: ${pattern}
  ${flags ? `Flags: ${flags}` : ''}
  ${includeExamples ? 'Include example matches and non-matches.' : ''}
  
  Provide your response as JSON:
  {
    "pattern": "${pattern}",
    "explanation": "Plain English explanation",
    "breakdown": [
      {"part": "regex part", "meaning": "what it matches"}
    ],
    "examples": [
      {"input": "example text", "matches": true, "matchedPart": "matched portion"}
    ]
  }`;
  
      try {
        const responseText = await this.llmWrapper.callToolLlm(
          'regex_helper',
          [
            { role: 'system', content: prompt },
            { role: 'user', content: `Explain this regex: /${pattern}/${flags}` },
          ],
          { type: 'explain_regex', pattern, flags }
        );
  
        const parsed = this.parseJsonResponse(responseText, {
          pattern,
          explanation: responseText,
          breakdown: [],
          examples: [],
        });
  
        return {
          success: true,
          pattern,
          explanation: parsed.explanation || '',
          breakdown: parsed.breakdown || [],
          examples: parsed.examples || [],
        };
      } catch (error) {
        return {
          success: false,
          pattern,
          explanation: '',
          breakdown: [],
          examples: [],
          error: error instanceof Error ? error.message : 'Unknown error',
        };
      }
    }

• src/tools/code-assistance.ts:933-975 (handler)

  Implementation of generateRegex tool handler in CodeAssistanceTools class.

    async generateRegex(
      description: string,
      options?: {
        flavor?: 'javascript' | 'python' | 'pcre';
        examples?: string[];
      }
    ): Promise<GenerateRegexResult> {
      const flavor = options?.flavor ?? 'javascript';
  
      const prompt = `You are a regex expert. Generate a regular expression based on this description.
  
  Regex flavor: ${flavor}
  ${options?.examples ? `Examples that should match:\n${options.examples.join('\n')}` : ''}
  
  Provide your response as JSON:
  {
    "pattern": "the regex pattern (without delimiters)",
    "flags": "any flags like 'gi'",
    "explanation": "How the pattern works",
    "examples": [
      {"input": "example", "shouldMatch": true}
    ],
    "alternativePatterns": ["simpler or alternative patterns"]
  }`;
  
      try {
        const responseText = await this.llmWrapper.callToolLlm(
          'regex_helper',
          [
            { role: 'system', content: prompt },
            { role: 'user', content: `Generate a regex that matches: ${description}` },
          ],
          { type: 'generate_regex', flavor }
        );
  
        const parsed = this.parseJsonResponse(responseText, {
          pattern: '',
          explanation: responseText,
          examples: [],
        });
  
        return {
          success: true,