Letter, Uppercase (Lu)

• Use Unicode-aware libraries and APIs that recognize General_Category Lu for accurate checks.
• Normalize input to a canonical form (NFC) before processing case-related logic.
• Prefer explicit uppercase mappings when creating or comparing identifiers across scripts.
• Test edge cases such as letters from non-Latin scripts and supplementary planes.
• Document any assumptions about language-specific casing and update tests accordingly.

Background: Letter, Uppercase (Lu) includes all uppercase characters across scripts. It is used when rendering, sorting, and validating identifiers that must appear in uppercase. Integrate with existing text processing to ensure these code points are treated correctly across platforms.

Usage and pitfalls: Common pitfalls include assuming a single Latin alphabet, overlooking letters with decorative forms, or misapplying mappings in environments that lack full Unicode support. Lu is part of a broader categorization system that helps distinguish character roles. For designers and engineers, consider linking visuals to categories such as Arrows Block and Geometric Shapes Block when illustrating examples or testing typography.