symboltab

README

I've called this a "symbol table". It converts a string ID to an integer sequence number. The integers start at 1 and increase by 1 for each new unique string. The intention is to store a very large number of strings, so the library is light on GC.

The idea behind the symbol table is to convert string IDs into integer IDs that can then be used for fast comparison and array/slice lookups

Documentation

Overview

Package symboltab is a symbol table. It converts strings to sequence numbers. This is useful for things like graph algorithms, where IDs are stored and compared a lot.

symboltab is optimised for storing a lot of strings, so things are optimised for reducing work for the GC

Index

• type SymbolTab
  • func New(cap int) *SymbolTab
  • func (i *SymbolTab) Cap() int
  • func (i *SymbolTab) Len() int
  • func (i *SymbolTab) SequenceToString(seq int32) string
  • func (i *SymbolTab) StringToSequence(val string, addNew bool) (seq int32, found bool)
  • func (i *SymbolTab) SymbolSize() int

Examples

• SymbolTab

Types

type SymbolTab

type SymbolTab struct {
	// contains filtered or unexported fields
}

SymbolTab is the symbol table. Allocate it via New()

Example

st := SymbolTab{}
seq, found := st.StringToSequence("10293-ahdb-28383-555", true)
fmt.Println(found)
fmt.Println(st.SequenceToString(seq))

Output:
false
10293-ahdb-28383-555

func New

func New(cap int) *SymbolTab

New creates a new SymbolTab. cap is the initial capacity of the table - it will grow automatically when needed

func (*SymbolTab) Cap

func (i *SymbolTab) Cap() int

Cap returns the size of the SymbolTab table

func (*SymbolTab) Len

func (i *SymbolTab) Len() int

Len returns the number of unique strings stored

func (*SymbolTab) SequenceToString

func (i *SymbolTab) SequenceToString(seq int32) string

SequenceToString looks up a string by its sequence number. Obtain the sequence number for a string with StringToSequence

func (*SymbolTab) StringToSequence

func (i *SymbolTab) StringToSequence(val string, addNew bool) (seq int32, found bool)

StringToSequence looks up the string val and returns its sequence number seq. If val does not currently exist in the symbol table, it will add it if addNew is true. found indicates whether val was already present in the SymbolTab

func (*SymbolTab) SymbolSize

func (i *SymbolTab) SymbolSize() int

SymbolSize contains the approximate size of string storage in the symboltable. This will be an over-estimate and includes as yet unused and wasted space