1 files changed, 0 insertions, 117 deletions
diff --git a/src/urubu/grammar/production.go b/src/urubu/grammar/production.go
deleted file mode 100644
index 8f6c103..0000000
--- a/src/urubu/grammar/production.go
+++ /dev/null
@@ -1,117 +0,0 @@
-package grammar
-
-import (
-	"crypto/sha256"
-	"encoding/hex"
-	"fmt"
-
-	"urubu/grammar/symbol"
-)
-
-type productionID [32]byte
-
-func (id productionID) String() string {
-	return hex.EncodeToString(id[:])
-}
-
-func genProductionID(lhs symbol.Symbol, rhs []symbol.Symbol) productionID {
-	seq := lhs.Byte()
-	for _, sym := range rhs {
-		seq = append(seq, sym.Byte()...)
-	}
-	return productionID(sha256.Sum256(seq))
-}
-
-type productionNum uint16
-
-const (
-	productionNumNil   = productionNum(0)
-	productionNumStart = productionNum(1)
-	productionNumMin   = productionNum(2)
-)
-
-func (n productionNum) Int() int {
-	return int(n)
-}
-
-type production struct {
-	id     productionID
-	num    productionNum
-	lhs    symbol.Symbol
-	rhs    []symbol.Symbol
-	rhsLen int
-}
-
-func newProduction(lhs symbol.Symbol, rhs []symbol.Symbol) (*production, error) {
-	if lhs.IsNil() {
-		return nil, fmt.Errorf("LHS must be a non-nil symbol; LHS: %v, RHS: %v", lhs, rhs)
-	}
-	for _, sym := range rhs {
-		if sym.IsNil() {
-			return nil, fmt.Errorf("a symbol of RHS must be a non-nil symbol; LHS: %v, RHS: %v", lhs, rhs)
-		}
-	}
-
-	return &production{
-		id:     genProductionID(lhs, rhs),
-		lhs:    lhs,
-		rhs:    rhs,
-		rhsLen: len(rhs),
-	}, nil
-}
-
-func (p *production) isEmpty() bool {
-	return p.rhsLen == 0
-}
-
-type productionSet struct {
-	lhs2Prods map[symbol.Symbol][]*production
-	id2Prod   map[productionID]*production
-	num       productionNum
-}
-
-func newProductionSet() *productionSet {
-	return &productionSet{
-		lhs2Prods: map[symbol.Symbol][]*production{},
-		id2Prod:   map[productionID]*production{},
-		num:       productionNumMin,
-	}
-}
-
-func (ps *productionSet) append(prod *production) {
-	if _, ok := ps.id2Prod[prod.id]; ok {
-		return
-	}
-
-	if prod.lhs.IsStart() {
-		prod.num = productionNumStart
-	} else {
-		prod.num = ps.num
-		ps.num++
-	}
-
-	if prods, ok := ps.lhs2Prods[prod.lhs]; ok {
-		ps.lhs2Prods[prod.lhs] = append(prods, prod)
-	} else {
-		ps.lhs2Prods[prod.lhs] = []*production{prod}
-	}
-	ps.id2Prod[prod.id] = prod
-}
-
-func (ps *productionSet) findByID(id productionID) (*production, bool) {
-	prod, ok := ps.id2Prod[id]
-	return prod, ok
-}
-
-func (ps *productionSet) findByLHS(lhs symbol.Symbol) ([]*production, bool) {
-	if lhs.IsNil() {
-		return nil, false
-	}
-
-	prods, ok := ps.lhs2Prods[lhs]
-	return prods, ok
-}
-
-func (ps *productionSet) getAllProductions() map[productionID]*production {
-	return ps.id2Prod
-}