🚀 Tempo Performance Benchmarks

To ensure high performance in mass-instantiation scenarios, Tempo implements a "Zero-Cost Constructor" architecture using prototype shadowing and lazy delegation. This document outlines the benchmark results for these optimizations.

📊 Summary of Timings

Timings were captured over 1,000 iterations to measure micro-overhead and compare different instantiation strategies.

Method	Total Time	µs / op	Notes
Default (Lazy Proxy)	523.14ms	523.14µs	Current $O(1)$ constructor.
Eager Simulation	1394.51ms	1394.51µs	~2.7x slower (simulating pre-refactor impact).
Fast-Fail @sync	359.04ms	359.04µs	Rejected instantly by the Master Guard.
Object.create Baseline	0.22ms	0.22µs	Raw JS overhead for comparison.

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🏗️ Architectural Impact

1. Proxy-Delegator Delegation ($O(1)$)

By using a Proxy-Delegator pattern, the constructor returns near-instantly without populating the formatting (fmt) or term (term) objects. These registries are only discovered and memoized on the first property access.

• Gain: ~65% reduction in instantiation overhead.
• v2.1.2 Update: The Scan-and-Consume guard further stabilizes the "Zero-Cost Constructor" by ensuring that even with massive plugin lists, the entry-point remains $O(1)$.

2. The Master Guard (Fast-Fail)

The static #guard regex acts as a rapid "Sync Point."

• Efficiency: Strings that do not contain valid date-time characters are rejected in $O(1)$ time.
• Performance: Validating a string against the guard is ~30% faster than a full parsing cycle, even for simple ISO strings.

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🧪 Benchmark Methodology

The benchmark script used performance.now() within a Vitest environment to ensure accurate module resolution and internal alias support (#library).

1. Lazy Creation: Creates a new Tempo('2024-05-20') without accessing any properties.
2. Eager Simulation: Creates a new Tempo() and manually triggers discovery on 5 core properties to simulate $O(N)$ initialization.
3. Invalid Parse: Passes a string that fails the Master Guard (e.g., includes emojis or exotic symbols) to measure rejection speed.

INFO

These benchmarks represent the library's performance under Node.js v22+. Results may vary based on the JS engine (V8, JavaScriptCore, etc.) but the $O(1)$ complexity remains constant.