Handle circular references

[ghostwriter]

This patch resolves #4 , via the following changes:

• Files changed

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 80.90909% with 21 lines in your changes missing coverage. Please review.

Project coverage is 81.20%. Comparing base (0de6d8d) to head (45c9099).
Report is 2 commits behind head on main.

✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
src/Builder.php	79.38%	20 Missing ⚠️
src/Lexer.php	83.33%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main       #5      +/-   ##
============================================
- Coverage     83.33%   81.20%   -2.13%     
- Complexity       14       38      +24     
============================================
  Files             3        4       +1     
  Lines            78      149      +71     
============================================
+ Hits             65      121      +56     
- Misses           13       28      +15     

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