symbol — interned, immutable identifier

github.com/go-composites/symbol (Go package Symbol, imported from the src/ sub-directory) is the org's equivalent of Ruby's Symbol (:name): an interned, immutable identifier. Two symbols built from the same name are the same underlying instance, so Symbol.New("x") == Symbol.New("x") and identity comparison is meaningful and cheap. The registry is guarded by a sync.Mutex, making interning safe for concurrent callers.

API

import Symbol "github.com/go-composites/symbol/src"

type Interface interface {
    ToGoString() string
    Name() string
    Equal(Interface) bool
    IsNull() bool
    Inspect() string
}

func New(name string) Interface
func Null() Interface

New(name) returns the interned symbol for name; calling it again with the same name yields the same instance.
Null() returns the Null-Object symbol (see below).

Member	Behaviour
`ToGoString()`	Returns the symbol's name as a Go string.
`Name()`	An alias for `ToGoString()`.
`Equal(other)`	Reports whether `other` denotes the same interned name. Because symbols are interned this is equivalent to pointer identity for real symbols; comparing names also makes it robust against the Null-Object (a null symbol is never equal).
`IsNull()`	Returns `false` for a real symbol, `true` for the `Null()` one.
`Inspect()`	Renders the symbol as the literal `:name`.

Usage

a := Symbol.New("status")
b := Symbol.New("status")

fmt.Println(a == b)          // true — interned, same instance
fmt.Println(a.Equal(b))      // true
fmt.Println(a.Name())        // status
fmt.Println(a.Inspect())     // :status

The Null-Object variant

Symbol.Null() honours the full Interface without ever being nil: it has an empty name (ToGoString()/Name() return ""), is never equal to any symbol — including itself — Inspect() renders :null, and IsNull() returns true.

Dependencies

symbol has no intra-org dependencies — it builds only on the Go standard library (fmt, sync).