Design¶

Design decision records for Z3Wire. Each document captures a tricky design space, the reasoning behind the decisions made, and alternatives considered.

• Concrete Types — why concrete types exist, why they have minimal operations, and their role as typed data holders
• Bool vs UInt<1> — why booleans and 1-bit vectors are separate types with explicit conversion
• Lossless Auto-Promotion — which type conversions happen implicitly, which require explicit casts, and why
• Three-Tier Casting — why there are three cast functions and when to use each
• Comparison Semantics — why comparison operators are strict on width and signedness, and why mathematical comparisons use the z3w::math_* free-function family
• Bit-Growth Arithmetic — why arithmetic and left shift widen their result types instead of wrapping