obitools4/autodoc/docmd/pkg/obitax/inner.md

obitax Package: String Interning with Thread-Safe Storage

This Go package (obitax) provides a thread-safe string interner—a data structure that deduplicates identical strings by storing only one copy per unique value and returning shared references.

Core Components

• InnerString struct
  Holds:

  • index: A map from string values to pointers (ensuring identity via pointer equality).
  • lock: An embedded sync.RWMutex to guarantee safe concurrent access.

• Constructor: NewInnerString()
  Initializes an empty interner with a preallocated map.

• Method: Innerize(value string) *string

  • Stores a new unique value (after cloning via strings.Clone) if absent.
  • Returns the pointer to either:
    • The newly interned string, or
    • An existing one (if already present).
  • Ensures no duplicate string data is stored for equal values.
  • Fully thread-safe via write lock.

• Method: Slice() []string
  Returns a snapshot of all interned strings as a slice (copying values, not pointers).

  • Not safe for concurrent writes during iteration.
  • Suitable for inspection or debugging.

Semantic Use Cases

• Memory optimization: Avoid repeated allocation of identical strings (e.g., in parsing, serialization).
• Pointer-based identity checks: Use == on returned pointers to test string equality efficiently.
• Concurrent safety: Designed for use in multi-goroutine environments (e.g., HTTP servers, pipelines).

Design Notes

• Uses strings.Clone() to decouple interned strings from original input lifetimes.
• Interning is append-only—no removal mechanism provided (implied by semantics of a simple interner).
• Returns *string to enable fast equality comparisons and reduce memory footprint.

Note

: This is a minimal, efficient interner—ideal for read-heavy or batched deduplication scenarios.