Merge pull request #137 from pointlander/set

Removed jetset dependency and added internal set type

go.mod

@@ -1,5 +1,3 @@
 module github.com/pointlander/peg
 
-require github.com/pointlander/jetset v1.0.1-0.20190518214125-eee7eff80bd4
-
 go 1.13

go.sum

@@ -1,8 +0,0 @@
-github.com/pointlander/compress v1.1.0 h1:5fUcQV2qEHvk0OpILH6eltwluN5VnwiYrkc1wjGUHnU=
-github.com/pointlander/compress v1.1.0/go.mod h1:q5NXNGzqj5uPnVuhGkZfmgHqNUhf15VLi6L9kW0VEc0=
-github.com/pointlander/compress v1.1.1-0.20190518213731-ff44bd196cc3 h1:hUmXhbljNFtrH5hzV9kiRoddZ5nfPTq3K0Sb2hYYiqE=
-github.com/pointlander/compress v1.1.1-0.20190518213731-ff44bd196cc3/go.mod h1:q5NXNGzqj5uPnVuhGkZfmgHqNUhf15VLi6L9kW0VEc0=
-github.com/pointlander/jetset v1.0.0 h1:bNlaNAX7cDPID9SlcogmXlDWq0KcRJSpKwHXaAM3bGQ=
-github.com/pointlander/jetset v1.0.0/go.mod h1:zY6+WHRPB10uzTajloHtybSicLW1bf6Rz0eSaU9Deng=
-github.com/pointlander/jetset v1.0.1-0.20190518214125-eee7eff80bd4 h1:RHHRCZeaNyBXdYPMjZNH8/XHDBH38TZzw8izrW7dmBE=
-github.com/pointlander/jetset v1.0.1-0.20190518214125-eee7eff80bd4/go.mod h1:RdR1j20Aj5pB6+fw6Y9Ur7lMHpegTEjY1vc19hEZL40=

set/set.go

@@ -0,0 +1,318 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package set
+
+import (
+	"fmt"
+	"math"
+)
+
+// Node is a node
+type Node struct {
+	Forward  *Node
+	Backward *Node
+	Begin    rune
+	End      rune
+}
+
+// Set is a set
+type Set struct {
+	Head Node
+	Tail Node
+}
+
+// NewSet returns a new set
+func NewSet() *Set {
+	return &Set{
+		Head: Node{
+			Begin: math.MaxInt32,
+		},
+	}
+}
+
+// String returns the string of a set
+func (s *Set) String() string {
+	codes, space := "[", ""
+	node := s.Head.Forward
+	for node.Forward != nil {
+		for code := node.Begin; code <= node.End; code++ {
+			codes += space + fmt.Sprintf("%v", code)
+			space = " "
+		}
+		node = node.Forward
+	}
+	return codes + "]"
+}
+
+// Copy copies a set
+func (s *Set) Copy() *Set {
+	set := NewSet()
+	if s.Head.Forward == nil {
+		return set
+	}
+	a, b := s.Head.Forward, &set.Head
+	for a.Forward != nil {
+		node := Node{
+			Backward: b,
+			Begin:    a.Begin,
+			End:      a.End,
+		}
+		b.Forward = &node
+		a = a.Forward
+		b = b.Forward
+	}
+	b.Forward = &set.Tail
+	set.Tail.Backward = b
+	return set
+}
+
+// Add adds a symbol to the set
+func (s *Set) Add(a rune) {
+	s.AddRange(a, a)
+}
+
+// AddRange adds to a set
+func (s *Set) AddRange(begin, end rune) {
+	beginNode := &s.Head
+	for beginNode.Forward != nil && begin > beginNode.Forward.End {
+		beginNode = beginNode.Forward
+	}
+	endNode := &s.Tail
+	for endNode.Backward != nil && end < endNode.Backward.Begin {
+		endNode = endNode.Backward
+	}
+	if beginNode.Forward == nil && endNode.Backward == nil {
+		node := Node{
+			Begin: begin,
+			End:   end,
+		}
+		node.Forward = endNode
+		endNode.Backward = &node
+		node.Backward = beginNode
+		beginNode.Forward = &node
+	} else if beginNode.Forward == endNode.Backward {
+		if begin < beginNode.Forward.Begin {
+			beginNode.Forward.Begin = begin
+		}
+		if end > beginNode.Forward.End {
+			beginNode.Forward.End = end
+		}
+	} else if beginNode.Forward != nil && endNode.Backward == nil {
+		node := Node{
+			Begin: begin,
+			End:   end,
+		}
+		node.Backward = beginNode
+		node.Forward = beginNode.Forward
+		beginNode.Forward.Backward = &node
+		beginNode.Forward = &node
+	} else if beginNode.Forward == nil && endNode.Backward != nil {
+		node := Node{
+			Begin: begin,
+			End:   end,
+		}
+		node.Forward = endNode
+		node.Backward = endNode.Backward
+		endNode.Backward.Forward = &node
+		endNode.Backward = &node
+	} else if beginNode.Forward == endNode {
+		node := Node{
+			Begin: begin,
+			End:   end,
+		}
+		node.Backward = beginNode
+		node.Forward = beginNode.Forward
+		beginNode.Forward.Backward = &node
+		beginNode.Forward = &node
+	} else if beginNode == endNode.Backward {
+		node := Node{
+			Begin: begin,
+			End:   end,
+		}
+		node.Forward = endNode
+		node.Backward = endNode.Backward
+		endNode.Backward.Forward = &node
+		endNode.Backward = &node
+	} else {
+		if begin < beginNode.Forward.Begin {
+			beginNode.Forward.Begin = begin
+		}
+		if end > endNode.Backward.End {
+			beginNode.Forward.End = end
+		} else {
+			beginNode.Forward.End = endNode.Backward.End
+		}
+		node := beginNode.Forward
+		node.Forward = endNode
+		endNode.Backward = node
+	}
+}
+
+// Has tests if a set has a rune
+func (s *Set) Has(begin rune) bool {
+	beginNode := &s.Head
+	for beginNode.Forward != nil && begin > beginNode.Forward.End {
+		beginNode = beginNode.Forward
+	}
+	if beginNode.Forward == nil {
+		return false
+	}
+	return begin >= beginNode.Forward.Begin
+}
+
+// Complement computes the complement of a set
+func (s *Set) Complement(endSymbol rune) *Set {
+	set := NewSet()
+	if s.Len() == 0 {
+		node := Node{
+			Forward:  &set.Tail,
+			Backward: &set.Head,
+			Begin:    0,
+			End:      endSymbol,
+		}
+		set.Head.Forward = &node
+		set.Tail.Backward = &node
+		return set
+	}
+	if s.Head.Forward.Begin == 0 && s.Head.Forward.End == endSymbol {
+		return set
+	}
+	a, b := &s.Head, &set.Head
+	if a.Forward.Begin == 0 && s.Tail.Backward.End == endSymbol {
+		a = a.Forward
+		pre := a.End + 1
+		a = a.Forward
+		for a.Forward != nil {
+			node := Node{
+				Backward: b,
+				Begin:    pre,
+				End:      a.Begin - 1,
+			}
+			pre = a.End + 1
+			b.Forward = &node
+			a = a.Forward
+			b = b.Forward
+		}
+		b.Forward = &set.Tail
+		set.Tail.Backward = b
+	} else {
+		pre := rune(0)
+		a = a.Forward
+		for a.Forward != nil {
+			node := Node{
+				Backward: b,
+				Begin:    pre,
+				End:      a.Begin - 1,
+			}
+			pre = a.End + 1
+			b.Forward = &node
+			a = a.Forward
+			b = b.Forward
+		}
+		node := Node{
+			Backward: b,
+			Begin:    pre,
+			End:      endSymbol,
+		}
+		b.Forward = &node
+		b = b.Forward
+		b.Forward = &set.Tail
+		set.Tail.Backward = b
+	}
+	return set
+}
+
+// Union is the union of two sets
+func (s *Set) Union(a *Set) *Set {
+	set := s.Copy()
+	node := a.Head.Forward
+	if node == nil {
+		return set
+	}
+	for node.Forward != nil {
+		set.AddRange(node.Begin, node.End)
+		node = node.Forward
+	}
+	return set
+}
+
+// Intersects returns true if two sets intersect
+func (a *Set) Intersects(b *Set) bool {
+	x := a.Head.Forward
+	if x == nil {
+		return false
+	}
+	for x.Forward != nil {
+		y := b.Head.Forward
+		if y == nil {
+			return false
+		}
+		for y.Forward != nil {
+			if y.Begin >= x.Begin && y.Begin <= x.End {
+				return true
+			} else if y.End >= x.Begin && y.End <= x.End {
+				return true
+			}
+			y = y.Forward
+		}
+		x = x.Forward
+	}
+	x = b.Head.Forward
+	if x == nil {
+		return false
+	}
+	for x.Forward != nil {
+		y := a.Head.Forward
+		if y == nil {
+			return false
+		}
+		for y.Forward != nil {
+			if y.Begin >= x.Begin && y.Begin <= x.End {
+				return true
+			} else if y.End >= x.Begin && y.End <= x.End {
+				return true
+			}
+			y = y.Forward
+		}
+		x = x.Forward
+	}
+	return false
+}
+
+// Equal returns true if two sets are equal
+func (s *Set) Equal(a *Set) bool {
+	lens, lena := s.Len(), a.Len()
+	if lens != lena {
+		return false
+	} else if lens == 0 && lena == 0 {
+		return true
+	}
+	x, y := s.Head.Forward, a.Head.Forward
+	for {
+		if x.Begin != y.Begin || x.End != y.End {
+			fmt.Println(x.Begin, x.End, y.Begin, y.End)
+			return false
+		}
+		x, y = x.Forward, y.Forward
+		if x == nil && y == nil {
+			break
+		}
+	}
+	return true
+}
+
+// Len returns the size of the set
+func (s *Set) Len() int {
+	size := 0
+	if s.Head.Forward == nil {
+		return size
+	}
+	beginNode := s.Head.Forward
+	for beginNode.Forward != nil {
+		size += int(beginNode.End) - int(beginNode.Begin) + 1
+		beginNode = beginNode.Forward
+	}
+	return size
+}